Granted (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period Receivable Type [Axis] Receivable Type [Axis] Aggregate Intrinsic Value, Outstanding Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Intrinsic Value Schedule of loans modified under the terms of a TDR, including TDR loans that defaulted Financing Receivable, Troubled Debt Restructuring [Table Text Block] State and political subdivisions US States and Political Subdivisions Debt Securities [Member] Non-PCD loans: Business Combination, Acquired Receivables [Abstract] Commitments and Contingencies Commitments and Contingencies Disclosure [Text Block] Subordinated debentures Subordinated Debt [Member] Common equity tier 1 capital, Well Capitalized Common Equity Tier 1 Capital Required To Be Well Capitalized To Risk Weighted Assets Common Equity Tier 1 Capital Required To Be Well Capitalized To Risk Weighted Assets. Cash flow hedge Interest Rate Cash Flow Hedge Asset at Fair Value Securities Investments in Debt and Marketable Equity Securities (and Certain Trading Assets) Disclosure [Text Block] Mortgage banking - loan commitment Mortgage Banking Loan Commitment [Member] Represents information of mortgage banking - loan commitment. Service charges and fees Deposit Account [Member] Estimated Aggregate Amortization Expense For Future Periods Finite-Lived Intangible Assets, Net, Amortization Expense, Fiscal Year Maturity [Abstract] Remainder of 2020 Sales-Type and Direct Financing Leases, Lease Receivable, to be Received, Remainder of Fiscal Year Statistical Measurement [Domain] Statistical Measurement [Domain] LIABILITIES AND SHAREHOLDERS’ EQUITY Liabilities and Equity [Abstract] Share-based Compensation Arrangement by Share-based Payment Award [Line Items] Share-based Compensation Arrangement by Share-based Payment Award [Line Items] Share-based Compensation Arrangement by Share-based Payment Award [Line Items] 2025 subordinated debentures Two Thousand Twenty Five Subordinated Debentures [Member] Represents information of 2025 subordinated debentures. Salaries and employee benefits Salaries and employee benefits expense Labor and Related Expense Common equity tier 1 capital Banking Regulation, Common Equity Tier One Risk-Based Capital Ratio, Actual Preferred Stock Preferred Stock [Member] Security Exchange Name Security Exchange Name Short-term deferrals related to COVID-19 crisis Financing Receivable, COVID Related Deferral Financing Receivable, COVID Related Deferral Gains from sales of other loans Gain (Loss) on Sale of Loans and Leases Reclassification from nonaccretable difference Certain Loans Acquired in Transfer Accounted for as Debt Securities, Accretable Yield, Reclassifications from Nonaccretable Difference Loans held for sale Increase (Decrease) in Loans Held-for-sale Reclassifications Out of Accumulated Other Comprehensive Income Reclassification out of Accumulated Other Comprehensive Income [Member] Available-for-Sale, Amortized Cost Debt Securities, Available-for-sale, Maturity, Amortized Cost, Rolling Maturity [Abstract] Net increase in deposits Increase (Decrease) in Deposits Outstanding, beginning balance (in dollars per share) Outstanding, ending balance (in dollars per share) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value Variable Rate [Domain] Variable Rate [Domain] Brokered time deposits Brokered Certificate Of Deposit [Member] Represents the brokered certificate of deposits. Gross losses on sales Debt Securities, Available-for-sale, Realized Loss Aggregate fair value adjustments Aggregate Fair Value Adjustments Represents aggregate fair value adjustments. Vesting of restricted stock unit awards, net of shares surrendered to cover payroll taxes Stock Issued During Period, Value, Restricted Stock Award, Net of Forfeitures ASSETS Assets [Abstract] Accounting Policies [Abstract] Accounting Policies [Abstract] Tier 1 capital, Minimum Banking Regulation, Tier One Risk-Based Capital Ratio, Capital Adequacy, Minimum United Community Bank Subsidiaries [Member] Common stock issued from deferred compensation plan, net of shares surrendered to cover payroll taxes Shares Issued, Value, Share-based Payment Arrangement, after Forfeiture Outstanding balance of PCI loans Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Outstanding Balance Unrealized holding losses on derivatives arising during the period, Net of Tax Amount Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), before Reclassification, after Tax Expected useful life of acquired intangible (in years) Acquired Finite-lived Intangible Assets, Weighted Average Useful Life 2021 Lessee, Operating Lease, Liability, to be Paid, Year One Outstanding, beginning balance (in shares) Outstanding, ending balance (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number 2024 Lessee, Operating Lease, Liability, to be Paid, Year Four Schedule of assets and liabilities measured at fair value on a recurring basis Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis [Table Text Block] Unrecognized compensation expense Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount Dividends and undistributed earnings allocated to unvested shares Undistributed Earnings (Loss) Allocated to Participating Securities, Basic New Accounting Pronouncements or Change in Accounting Principle [Line Items] New Accounting Pronouncements or Change in Accounting Principle [Line Items] Preferred stock issued Preferred Stock, Value, Issued Residential Residential Portfolio Segment [Member] Probable exposure rate Measurement Input, Probable Exposure Rate [Member] Measurement Input, Probable Exposure Rate [Member] Other comprehensive income (loss): Other Comprehensive Income (Loss), Net of Tax [Abstract] Common stock, par value (in dollars per share) Common Stock, Par or Stated Value Per Share Net deferred tax asset Deferred Income Tax Assets, Net Four Oaks Statutory Trust I Four Oaks Statutory Trust I [Member] Represents information about Four Oaks Statutory Trust I. Recorded Investment, With allowance recorded Impaired Financing Receivable, with Related Allowance, Recorded Investment Mortgage loan revenue Mortgage Loan Revenue [Member] Information of mortgage loan revenue. Advertising and public relations Marketing and Advertising Expense Measurement Frequency [Domain] Measurement Frequency [Domain] Current Loans Financing Receivable, Not Past Due Plan exercisable period Share-based Compensation Arrangement by Share-based Payment Award, Expiration Period Derivatives designated as hedging instruments Derivative Instruments in Hedges, Liabilities, at Fair Value Statement [Line Items] Statement [Line Items] Class of Stock [Domain] Class of Stock [Domain] Loans and Leases and Allowance for Credit Losses Loans, Notes, Trade and Other Receivables Disclosure [Text Block] Reclassifications Out of Accumulated Other Comprehensive Income Disclosure of Reclassification Amount [Text Block] Measurement Input Type [Domain] Measurement Input Type [Domain] Statement [Table] Statement [Table] Statistical Measurement [Axis] Statistical Measurement [Axis] Mortgage banking - forward sales commitment Mortgage Banking Forward Sales Commitment [Member] Represents mortgage banking - forward sales commitment. Risk-weighted assets Banking Regulation, Risk-Weighted Assets, Actual De-designated hedges De Designated Cash Flow Hedge [Member] Represents de-designated cash flow hedge. Regulatory Matters Regulatory Capital Requirements under Banking Regulations [Text Block] Nonrecurring Fair Value, Nonrecurring [Member] Weighted Average Weighted Average [Member] Risk category of loans by class of loans Risk Category Of Loans By Class Of Loans [Abstract] Risk category of loans by class of loans. Carrying amount of Assets (Liabilities) Hedged Liability, Fair Value Hedge Reclassification of losses on derivative instruments realized in net income, Before-tax Amount Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), Reclassification, before Tax Debt Securities Marketable Securities, Policy [Policy Text Block] Entity Small Business Entity Small Business Fair Value Hierarchy and NAV [Domain] Fair Value Hierarchy and NAV [Domain] Purchases Payments to Acquire Held-to-maturity Securities Total interest revenue Investment securities interest revenue Interest and Dividend Income, Operating Cash Basis Interest Revenue Received Impaired Financing Receivable, Interest Income, Cash Basis Method Amendment Flag Amendment Flag Deferred compensation plan, net, including dividend equivalents Deferred Compensation Plan Net Including Dividend Equivalents Represents the value of deferred compensation plan, net, including dividend equivalents. Weighted average common shares outstanding: Weighted average shares outstanding: Weighted Average Number of Shares Outstanding, Diluted [Abstract] Finite-Lived Intangible Assets, Major Class Name [Domain] Finite-Lived Intangible Assets, Major Class Name [Domain] Balance at beginning of period Balance at end of period Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Liability Value Additional awards remaining available under plan (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant Residential mortgage-backed securities, Agency Residential Mortgage-Backed Securities, Issued By US Government Sponsored Enterprises [Member] Debt securities collateralized by residential real estate mortgage loans (mortgages), issued by US Government Sponsored Enterprises, such as Federal Home Loan Mortgage Corporation (FHLMC or Freddie Mac). Reclassification of losses on derivative instruments realized in net income, Net of Tax Amount Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), Reclassification, after Tax Schedule of minimum future lease payments expected to be received from lease contracts Sales-type and Direct Financing Leases, Lease Receivable, Maturity [Table Text Block] Measurement Frequency [Axis] Measurement Frequency [Axis] Sales and settlements Fair Value Measurement With Unobservable Inputs Reconciliation, Recurring Basis, Liability, Sales And Settlements Fair Value Measurement With Unobservable Inputs Reconciliation, Recurring Basis, Liability, Sales And Settlements Financial Instruments [Domain] Financial Instruments [Domain] Allowance for Credit Losses - Held-to-Maturity and Available-for-Sale Securities and Off-Balance Sheet Credit Exposures Credit Loss, Financial Instrument [Policy Text Block] Schedule of carrying amount and fair values for other financial instruments that are not measured at fair value on a recurring basis Fair Value, by Balance Sheet Grouping [Table Text Block] Amount of Gain (Loss) Recognized in Income on Derivatives Derivative, Gain (Loss) on Derivative, Net Fair Value Measurement [Domain] Fair Value Measurement [Domain] Commitment for additional fund Commitment For Additional Fund Represents commitment for additional fund. Unpaid Principal Balance, With an allowance recorded Impaired Financing Receivable, with Related Allowance, Unpaid Principal Balance Fair Value, 12 Months or More Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer Subsequent Events Subsequent Events [Text Block] Derivative Liability [Abstract] Derivative Liability [Abstract] Investment securities, tax exempt Interest Income, Securities, Operating, Tax Exempt Marketable Securities [Line Items] Marketable Securities [Line Items] Loans, including fees Interest and Fee Income, Loans and Leases Fair Value, Total Debt Securities, Held-to-maturity, Unrealized Loss Position, Fair Value Financing Receivable, Credit Quality Indicator [Line Items] Financing Receivable, Credit Quality Indicator [Line Items] Financing Receivable, Credit Quality Indicator [Line Items] Interest-bearing deposits in banks Interest-bearing Deposits in Banks and Other Financial Institutions Schedule of restricted stock unit activity Share-based Payment Arrangement, Restricted Stock and Restricted Stock Unit, Activity [Table Text Block] 2018 Financing Receivable, Year Three, Originated, Two Years before Current Fiscal Year Schedule of debt securities held to maturity in an unrealized loss position Unrealized Gain Loss On Held To Maturity Securities [Table Text Block] Unrealized gain loss on held to maturity securities. Common stock issued for acquisition Stock Issued During Period, Value, Acquisitions Income Statement Location [Domain] Income Statement Location [Domain] 2022 Lessee, Operating Lease, Liability, to be Paid, Year Two Issue Date Debt Instrument Issue Year This element represents debt instrument issue year. Salaries and employee benefits expense Salaries And Employee Benefit Expense [Member] Salaries And Employee Benefit Expense Financing activities: Net Cash Provided by (Used in) Financing Activities [Abstract] Held-to-maturity debt securities Held-to-maturity Securities [Member] Merger-related and other charges Merger-Related And Other Costs [Member] Merger-Related And Other Costs Initial direct costs Sales Type And Direct Financing Leases, Initial Direct Costs Sales Type And Direct Financing Leases, Initial Direct Costs Schedule of operating lease income and expense and other supplemental information Lease, Cost [Table Text Block] 2023 Lessee, Operating Lease, Liability, to be Paid, Year Three 2024 Sales-Type and Direct Financing Leases, Lease Receivable, to be Received, Year Four Tier 1 capital Banking Regulation, Tier One Risk-Based Capital, Actual Total assets Assets Additions Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Liability, Issuances Unrealized Loss, 12 Months or More Debt Securities, Held-to-maturity, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss Outstanding, beginning balance (in shares) Outstanding, ending balance (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number Net increase in loans Payments to Acquire Loans and Leases Held-for-investment Subsequent Event Type [Axis] Subsequent Event Type [Axis] Antidilutive Securities [Axis] Antidilutive Securities [Axis] Loans Outstanding, Individually evaluated for impairment Financing Receivable, Individually Evaluated for Impairment Investments, Debt and Equity Securities [Abstract] Investments, Debt and Equity Securities [Abstract] Reclassification out of Accumulated Other Comprehensive Income [Axis] Reclassification out of Accumulated Other Comprehensive Income [Axis] Financing Receivable Portfolio Segment [Domain] Financing Receivable Portfolio Segment [Domain] Derivative assets & liabilities - risk participations Derivative Assets And Liabilities Risk Participations [Member] Derivative Assets And Liabilities Risk Participations Cash and cash equivalents Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Cash and Equivalents Thereafter Lessee, Operating Lease, Liability, Payments, Due After Year Four Lessee, Operating Lease, Liability, Payments, Due After Year Four Commercial mortgage-backed securities Commercial Mortgage Backed Securities [Member] Total allowance for credit losses, Charge-Offs Financing Receivable Allowance For Credit Loss And Off-Balance Sheet Credit Loss Liability, Writeoff Financing Receivable Allowance For Credit Loss And Off-Balance Sheet Credit Loss Liability, Writeoff Schedule of actual results and pro forma information Business Acquisition, Pro Forma Information, Nonrecurring Adjustments [Table Text Block] Total liabilities Liabilities Internal Credit Assessment [Domain] Internal Credit Assessment [Domain] Less discount Lessee, Operating Lease, Liability, Undiscounted Excess Amount Amounts related to interest settlements on derivatives Gain (Loss) On Derivative Interest Settlement Gain (Loss) On Derivative Interest Settlement Fair Value, Total Debt Securities, Available-for-sale, Unrealized Loss Position Commitments and Contingencies Disclosure [Abstract] Commitments and Contingencies Disclosure [Abstract] Level 1 Fair Value, Inputs, Level 1 [Member] Schedule of Accounts, Notes, Loans and Financing Receivable [Table] Schedule of Accounts, Notes, Loans and Financing Receivable [Table] Merger-related costs Acquisition-related Costs [Member] Average Balance Impaired Financing Receivable, Average Recorded Investment Residential mortgage servicing rights Residential Mortgage Servicing Rights [Member] Residential Mortgage Servicing Rights [Member] Bifurcated embedded derivatives and dealer offsets Bifurcated Embedded Derivatives And Dealer Offsets [Member] Bifurcated embedded derivatives and dealer offsets. Gains (losses) on fair value hedging relationships: Gain (Loss) on Fair Value Hedges Recognized in Earnings [Abstract] Fair Value, Less than 12 Months Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months Shares Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward] Servicing rights for SBA/USDA loans Servicing Asset at Fair Value, Amount Capital Surplus Additional Paid-in Capital [Member] Net interest revenue Interest Income (Expense), Net Deposits Deposit interest expense Interest Expense, Deposits Assets: Financial Instruments, Financial Assets, Balance Sheet Groupings [Abstract] Other assets Other Assets Derivative Liabilities Derivative Liability [Member] Represents Derivative Liability. Held-to-Maturity, Amortized Cost, Within 1 year Debt Securities, Held-to-Maturity, Amortized Cost, Maturity, Allocated and Single Maturity Date, Year One Nonrecurring Adjustment [Domain] Nonrecurring Adjustment [Domain] Asset Class [Axis] Asset Class [Axis] Outstanding principal balance Mortgage Loans Held For Sale Outstanding Principal Balance Represents mortgage loans held for sale quantified by principal amount, the principle balance held at close of period. Loans sold Financing Receivable, Sale Internal Credit Assessment [Axis] Internal Credit Assessment [Axis] Common stock outstanding (in shares) Common Stock, Shares, Outstanding Fair Value, 12 Months or More Debt Securities, Held-to-maturity, Continuous Unrealized Loss Position, 12 Months or Longer, Fair Value Available-for-Sale, Fair Value, More than 10 years Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, Rolling after 10 Years, Fair Value Actuarial losses Accumulated Defined Benefit Plans Adjustment, Net Gain (Loss) Attributable to Parent [Member] Home equity lines of credit Home Equity Line of Credit [Member] Outstanding, beginning balance (in dollars per share) Outstanding, ending balance (in dollars per share) Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price 2026 subordinated debentures Two Thousand Twenty Six Subordinated Debentures [Member] Two Thousand Twenty Six Subordinated Debentures Accounting Changes and Error Corrections [Abstract] Accounting Changes and Error Corrections [Abstract] Net cash received in (paid for) acquisition Payments to Acquire Businesses, Net of Cash Acquired Common stock authorized (in shares) Common Stock, Shares Authorized Schedule of minimum amounts required for capital adequacy purposes Schedule of Compliance with Regulatory Capital Requirements under Banking Regulations [Table Text Block] Dilutive securities (in shares) Incremental Common Shares Attributable to Dilutive Effect of Share-based Payment Arrangements Proceeds from exercise of stock options Proceeds from Stock Options Exercised Allowance for unfunded commitments, Collectively evaluated for impairment Off-Balance Sheet Liability, Credit Loss Liability, Collectively Evaluated For Impairment Off-Balance Sheet Liability, Credit Loss Liability, Collectively Evaluated For Impairment Debt securities Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Assets, Marketable Securities Increase in ACL Total allowance for credit losses, Beginning Balance Total allowance for credit losses, Ending Balance Total allowance for credit losses, Ending Balance Financing Receivable Allowance For Credit Loss And Off-Balance Sheet Credit Loss Liability Financing Receivable Allowance For Credit Loss And Off-Balance Sheet Credit Loss Liability Carrying value of PCI loans PCI Loans Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Carrying Amount, Net Comprehensive income, Tax (Expense) Benefit Comprehensive Income Loss Tax Represents amount of comprehensive income loss tax. Allowance for Loan Losses Allocated Impaired Financing Receivable, Related Allowance Income Statement [Abstract] Income Statement [Abstract] Accumulated Other Comprehensive Income (Loss) AOCI Attributable to Parent [Member] Schedule of amortized cost and fair value of available-for-sale and held-to-maturity securities by contractual maturity Investments Classified by Contractual Maturity Date [Table Text Block] Allowance for credit losses, held-to-maturity portfolio Debt Securities, Held-to-maturity, Allowance for Credit Loss 2022 senior debentures Two Thousand Twenty Two Senior Debentures [Member] Represents information of 2022 senior debentures. Schedule of loans held for sale at fair value under the fair value option Fair Value Option, Disclosures [Table Text Block] Debt Security Category [Axis] Debt Security Category [Axis] Unsettled securities purchases Unsettled Purchases Of Securities Available For Sale Unsettled Purchases Of Securities Available For Sale Consolidated Entities [Axis] Consolidated Entities [Axis] Securities (gains) losses, net Realized Investment Gains (Losses) Scenario [Domain] Scenario [Domain] Purchases of premises and equipment Payments to Acquire Property, Plant, and Equipment Mortgage Loans Held for Sale Mortgage Loans Held For Sale [Abstract] Mortgage Loans Held For Sale Long-term Debt Long-term Debt [Text Block] Goodwill and Other Intangible Assets Goodwill and Intangible Assets Disclosure [Text Block] Allowance for credit losses, available-for-sale portfolio Debt Securities, Available-for-sale, Allowance for Credit Loss Unrealized Loss, Total Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss Directors Director [Member] Amortization of losses included in net income on available-for-sale securities transferred to held-to-maturity, Net of Tax Amount Other Comprehensive Income, Reclassification Adjustment For Available For Sale Transferred To Held To Maturity Securities, After Tax Other Comprehensive Income, Reclassification Adjustment For Available For Sale Transferred To Held To Maturity Securities, After Tax Net income before income taxes Net income, Before-tax Amount Total before tax Income (Loss) from Continuing Operations before Equity Method Investments, Income Taxes, Noncontrolling Interest Hedging Designation [Axis] Hedging Designation [Axis] Reclassification out of Accumulated Other Comprehensive Income [Domain] Reclassification out of Accumulated Other Comprehensive Income [Domain] Accumulated Impairment Losses, beginning of period Accumulated Impairment Losses, end of period Goodwill, Impaired, Accumulated Impairment Loss Held-to-Maturity, Fair Value, 5 to 10 years Debt Securities, Held-to-maturity, Maturity, Allocated and Single Maturity Date, Rolling after Five Through Ten Years, Fair Value Proceeds from issuance of senior debentures, net of issuance costs Proceeds from Issuance of Senior Long-term Debt Operating lease liability, balance sheet Operating Lease, Liability, Statement of Financial Position [Extensible List] Equity securities with readily available fair values Equity Securities, FV-NI Security deposits Sales Type And Direct Financing Leases, Security Deposits Sales Type And Direct Financing Leases, Security Deposits Entity [Domain] Entity [Domain] Compensation expense related to acquisition Share-Based Compensation Arrangement By Share-Based Payment Award, Cost Related To Acquisition Share-Based Compensation Arrangement By Share-Based Payment Award, Cost Related To Acquisition Cash paid for shares withheld to cover payroll taxes upon vesting of restricted stock units Payment, Tax Withholding, Share-based Payment Arrangement Designated as hedging instrument Designated as Hedging Instrument [Member] Marketable Securities [Table] Marketable Securities [Table] Comprehensive income, Before-tax Amount Comprehensive Income Loss Before Tax Represents amount of comprehensive income (loss) before tax. Cash flow hedge of subordinated debt Interest Rate Contract. Subordinated Debt [Member] Interest Rate Contract. Subordinated Debt Acquisitions Goodwill, Acquired During Period Financing Receivable, Troubled Debt Restructuring [Line Items] Financing Receivable, Troubled Debt Restructuring [Line Items] Schedule of cost basis, unrealized gains and losses, and fair value of debt securities available for sale Debt Securities, Available-for-sale [Table Text Block] Number of Contracts Financing Receivable, Modifications, Number of Contracts Schedule of gains and losses recognized in income on derivatives not designated as hedging instruments Derivatives Not Designated as Hedging Instruments [Table Text Block] Reclassification adjustment for losses included in net income, Before-tax Amount Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI for Sale of Securities, before Tax Debt and Equity Securities, FV-NI [Line Items] Debt and Equity Securities, FV-NI [Line Items] Lessee, Lease, Description [Line Items] Lessee, Lease, Description [Line Items] Fair Value Disclosures [Abstract] Fair Value Disclosures [Abstract] Total capital Banking Regulation, Total Risk-Based Capital Ratio, Actual Equipment financing Equipment financing Equipment Financing [Member] Represents information related to equipment financing. Unrealized Loss, Total Debt Securities, Held-to-maturity, Unrealized Loss Position, Accumulated Loss Debt securities available-for-sale Debt securities available-for-sale, fair value Fair Value Debt Securities, Available-for-sale Loans Past Due Financing Receivable, Past Due Loans, net Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Assets, Receivables Share-based Payment Arrangement [Abstract] Share-based Payment Arrangement [Abstract] Consolidated Entities [Domain] Consolidated Entities [Domain] Loans Outstanding, Collectively evaluated for impairment Financing Receivable, Collectively Evaluated for Impairment Loans Past Due, over 90 Days Financial Asset, Equal to or Greater than 90 Days Past Due [Member] FDIC assessments and other regulatory charges Federal Deposit Insurance Corporation Premium Expense Class of Financing Receivable [Domain] Class of Financing Receivable [Domain] Cancelled (in dollars per share) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeitures, Weighted Average Grant Date Fair Value Derivative Instruments, Gain (Loss) [Line Items] Derivative Instruments, Gain (Loss) [Line Items] Derivative Instruments, Gain (Loss) [Line Items] Assets and Liabilities Measured at Fair Value Fair Value Disclosures [Text Block] Accounts, Notes, Loans and Financing Receivable [Line Items] Accounts, Notes, Loans and Financing Receivable [Line Items] Interest rate swaps Interest Rate Swap [Member] Derivatives, Fair Value [Line Items] Derivatives, Fair Value [Line Items] Adoption of new accounting standard Adoption of CECL Cumulative Effect, Period of Adoption, Adjustment [Member] Held-to-Maturity, Amortized Cost, 1 to 5 years Debt Securities, Held-to-Maturity, Amortized Cost, Maturity, Allocated and Single Maturity Date, after Year One Through Five Depreciation, amortization and accretion Depreciation, Amortization and Accretion, Net Preferred stock liquidation preference (in dollars per share) Preferred Stock, Liquidation Preference, Value Entity Registrant Name Entity Registrant Name Subsequent Event Type [Domain] Subsequent Event Type [Domain] Business Acquisition [Line Items] Business Acquisition [Line Items] Assets: Assets, Fair Value Disclosure [Abstract] Operating lease, weighted average discount rate (percent) Operating Lease, Weighted Average Discount Rate, Percent Long-term debt Long-term debt interest expense Interest Expense, Long-term Debt Common stock issued to dividend reinvestment plan and employee benefits plans (in shares) Stock Issued During Period Shares Dividend Reinvestment Plan and Employee Benefit Plans This element represents number of common stock issued to dividend reinvestment plan and employee benefit plans. Weighted- Average Exercise Price Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price [Abstract] Debt securities held-to-maturity: Debt Securities Held To Maturity [Abstract] Debt Securities Held To Maturity [Abstract] Total allowance for credit losses, Collectively evaluated for impairment Financing Receivable Allowance For Credit Loss And Off-Balance Sheet Credit Loss Liability, Collectively Evaluated For Impairment Financing Receivable Allowance For Credit Loss And Off-Balance Sheet Credit Loss Liability, Collectively Evaluated For Impairment Repayment of FHLB advances Payments of FHLBank Borrowings, Financing Activities Average total assets for the leverage ratio Regulatory Assets Pass Pass [Member] Cash dividends on common stock Payments of Ordinary Dividends, Common Stock Entity Incorporation, State or Country Code Entity Incorporation, State or Country Code Dividend date of record Dividends Payable, Date of Record Core deposit intangible Core Deposits [Member] Preferred Stock Dividends, Income Statement Impact Preferred Stock Dividends, Income Statement Impact Number of held-to-maturity debt securities in unrealized loss position Held-to-maturity, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions Adjustments for New Accounting Pronouncements [Axis] Accounting Standards Update [Axis] Gross Unrealized Losses Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax Entity Address, Postal Zip Code Entity Address, Postal Zip Code Goodwill Goodwill, net of Accumulated Impairment Losses, beginning of period Goodwill, net of Accumulated Impairment Losses, end of period Goodwill Deposits: Deposits [Abstract] Debt Securities, Available-for-sale [Line Items] Debt Securities, Available-for-sale [Line Items] Amortization of losses included in net income on available-for-sale securities transferred to held to maturity Accumulated Amortization Of Gains Included In Net Income On Available For Sale Securities Transferred To Held To Maturity [Member] Represents accumulated amortization of gains included in net income on available for sale securities transferred to held to maturity. Schedule of quantitative information about Level 3 fair value measurements for fair value on a recurring basis Fair Value Measurement Inputs and Valuation Techniques [Table Text Block] Total other comprehensive income, net of tax amount Other comprehensive income Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent 2021 Sales-Type and Direct Financing Leases, Lease Receivable, to be Received, Year One Purchases of common stock Stock Repurchased and Retired During Period, Value Common stock dividends (in dollars per share) Cash dividend declared per common share (in dollars per share) Common Stock, Dividends, Per Share, Declared Schedule of changes in the carrying amounts of goodwill Schedule of Goodwill [Table Text Block] Asset Class [Domain] Asset Class [Domain] Schedule of nonaccrual loans by loan class Financing Receivable, Nonaccrual [Table Text Block] Interest revenue: Interest and Dividend Income, Operating [Abstract] Equity [Abstract] Equity [Abstract] Total assets Loans Assets, Fair Value Disclosure Schedule of carrying amount and cumulative fair value hedging adjustments on hedged liability Schedule Of Fair Value Hedging Instruments, Carrying Value And Basis Adjustments [Table Text Block] Schedule Of Fair Value Hedging Instruments, Carrying Value And Basis Adjustments [Table Text Block] Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share [Table] Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share [Table] Debt Securities, Held-to-maturity [Table] Debt Securities, Held-to-maturity [Table] Significant non-cash investing and financing transactions: Cash Flow, Noncash Investing and Financing Activities Disclosure [Abstract] Net unrealized gains, Before-tax Amount Other Comprehensive Income Loss Unrealized Holding Gain Loss On Securities Net Of Reclassification and Valuation Allowance Arising During Period Before Tax Other comprehensive income loss unrealized holding gain loss on securities net of reclassification and valuation allowance arising during period before tax. Schedule of carrying amount of goodwill and other intangible assets Schedule of Intangible Assets and Goodwill [Table Text Block] Postage, printing and supplies Supplies and Postage Expense SOFR Secured Overnight Financing Rate (SOFR) Overnight Index Swap Rate [Member] Provision for credit losses Total allowance for credit losses, (Release) Provision Provision for Loan, Lease, and Other Losses Other Comprehensive Income (Loss), Defined Benefit Plan, Gain (Loss), Reclassification Adjustment from AOCI, Tax Other Comprehensive Income (Loss), Defined Benefit Plan, Gain (Loss), Reclassification Adjustment from AOCI, Tax Derivative Contract [Domain] Derivative Contract [Domain] Available-for-Sale, Fair Value, 1 to 5 years Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, Rolling after One Through Five Years, Fair Value Diluted (in shares) Diluted (in shares) Weighted Average Number of Shares Outstanding, Diluted Letters of credit Letter of Credit [Member] Cancelled (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeited in Period Debt Disclosure [Abstract] Debt Disclosure [Abstract] Right-of-use asset, balance sheet Operating Lease, Right-of-Use Asset, Statement of Financial Position [Extensible List] Net amount Derivative Liability, Fair Value, Offset Against Collateral, Net of Not Subject to Master Netting Arrangement, Policy Election Net cash provided by (used in) financing activities Net Cash Provided by (Used in) Financing Activities Post-Modification Outstanding Amortized Cost by Type of Modification Financing Receivable, Troubled Debt Restructuring, Postmodification Substandard Substandard [Member] Schedule of average balances of impaired loans and income recognized on impaired loans under Incurred Loss Average Balances Of Impaired Loans and Income Recognized On Impaired Loans [Table Text Block] Average balances of impaired loans and income recognized on impaired loans. Cash dividends on preferred stock Payments of Ordinary Dividends, Preferred Stock and Preference Stock Common stock, $1 par value: 150,000,000 shares authorized; 86,611,114 and 79,013,729 shares issued and outstanding, respectively Common Stock, Value, Issued Schedule of net investment in leases Schedule Of Components Of Net Investment In Lease, Sales Type And Direct Financing Leases [Table Text Block] Schedule Of Components Of Net Investment In Lease, Sales Type And Direct Financing Leases [Table Text Block] Document Fiscal Year Focus Document Fiscal Year Focus Net deferred tax asset Business Combination Recognized Identifiable Assets Acquired and Liabilities Assumed, Deferred Tax Assets 2022 Finite-Lived Intangible Asset, Expected Amortization, Year Two Total other comprehensive income, Tax (Expense) Benefit Other Comprehensive Income (Loss), Tax, Portion Attributable to Parent Total allowance for credit losses, Individually evaluated for impairment Financing Receivable Allowance For Credit Loss And Off-Balance Sheet Credit Loss Liability, Individually Evaluated For Impairment Financing Receivable Allowance For Credit Loss And Off-Balance Sheet Credit Loss Liability, Individually Evaluated For Impairment Entity Current Reporting Status Entity Current Reporting Status 2023 Sales-Type and Direct Financing Leases, Lease Receivable, to be Received, Year Three Amounts included in earnings - fair value adjustments Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Liability, Gain (Loss) Included in Earnings Available-for-sale debt securities Debt Securities Available-for-Sale Available-for-sale Securities [Member] Derivative Asset [Abstract] Derivative Asset [Abstract] Goodwill and other intangible assets, net Total goodwill and other intangible assets, net Intangible Assets, Net (Including Goodwill) Purchases Payments to Acquire Debt Securities, Available-for-sale Common stock issued (in shares) Common Stock, Shares, Issued Schedule of Impaired Financing Receivable [Table] Schedule of Impaired Financing Receivable [Table] Operating lease liability Present value of lease liability Operating Lease, Liability Total allowance for credit losses, Recoveries Financing Receivable Allowance For Credit Loss And Off-Balance Sheet Credit Loss Liability, Recovery Financing Receivable Allowance For Credit Loss And Off-Balance Sheet Credit Loss Liability, Recovery Realized gains (losses) reclassified from AOCI into net income Interest Rate Cash Flow Hedge Gain (Loss) Reclassified to Earnings, Net Debt Instrument [Line Items] Debt Instrument [Line Items] Total shareholders' equity Beginning balance Ending balance Reduction in equity Stockholders' Equity Attributable to Parent Schedule of Compliance with Regulatory Capital Requirements under Banking Regulations [Table] Schedule of Compliance with Regulatory Capital Requirements under Banking Regulations [Table] Total consideration Total fair value of consideration transferred Business Combination, Consideration Transferred Shares issued in acquisition (in shares) Common stock issued (in shares) Business Acquisition, Equity Interest Issued or Issuable, Number of Shares Repayment of long-term debt Repayments of Other Long-term Debt Entity Address, City or Town Entity Address, City or Town Fair Value Hierarchy and NAV [Axis] Fair Value Hierarchy and NAV [Axis] Restricted Stock Units Restricted stock units Restricted Stock Units (RSUs) [Member] Bank owned life insurance Bank Owned Life Insurance Financial Instrument [Axis] Financial Instrument [Axis] Par value Financing Receivable, Purchased with Credit Deterioration, Amount at Par Value Type of Adoption [Domain] Accounting Standards Update [Domain] Nonrecurring Adjustment [Axis] Nonrecurring Adjustment [Axis] Short-term lease cost Short-term Lease, Cost Held-to-Maturity, Amortized Cost, More than 10 years Debt Securities, Held-to-Maturity, Amortized Cost, Maturity, Allocated and Single Maturity Date, after Year 10 Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items] Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items] Customer derivatives, dealer offsets and risk participations Customer Derivatives, Dealer Offsets, And Risk Participations [Member] Customer Derivatives, Dealer Offsets, And Risk Participations Common equity tier 1 capital Banking Regulation, Common Equity Tier One Risk-Based Capital, Actual Liabilities: Liabilities [Abstract] Schedule of Available-for-sale Securities [Table] Schedule of Available-for-sale Securities [Table] Derivative assets and liabilities - other Derivative Assets And Liabilities Other [Member] Derivative Assets And Liabilities Other 2023 Finite-Lived Intangible Asset, Expected Amortization, Year Three Commercial & industrial Commercial And Industrial Classification [Member] Commercial And Industrial Classification[Member] Remainder of 2020 Lessee, Operating Lease, Liability, to be Paid, Remainder of Fiscal Year Total loans, excluding PCI loans Financing Receivable, Before Allowance For Credit Loss, Excluding Purchased Credit Impaired Loans Financing Receivable, Before Allowance For Credit Loss, Excluding Purchased Credit Impaired Loans Amortization of losses included in net income on available-for-sale securities transferred to held-to-maturity, Tax (Expense) Benefit Other Comprehensive Income, Reclassification Adjustment For Available For Sale Transferred To Held To Maturity Securities, Tax Other Comprehensive Income, Reclassification Adjustment For Available For Sale Transferred To Held To Maturity Securities, Tax Leases [Abstract] Leases [Abstract] Reclassification adjustment for losses included in net income, Tax (Expense) Benefit Income tax expense (benefit) attributable to sales Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI for Sale of Securities, Tax Other Other expense Other Noninterest Expense Long-term Debt, Type [Axis] Long-term Debt, Type [Axis] Sales and settlements Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Sales And Settlements Amount of sale and settlement of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing. Thereafter Finite-Lived Intangible Asset, Expected Amortization, After Year Four Finite-Lived Intangible Asset, Expected Amortization, After Year Four Number of derivative contracts Number of Interest Rate Derivatives Held Net income per common share: Earnings Per Share [Abstract] Earnings Per Share [Abstract] Net interest revenue after provision for credit losses Interest Income (Expense), after Provision for Loan Loss Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items] Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items] Net investment in leases Net investment in leases Net Investment in Lease Reclassifications related to defined benefit pension plan activity Accumulated Defined Benefit Plans Adjustment Attributable to Parent [Member] 2016 Financing Receivable, Year Five, Originated, Four Years before Current Fiscal Year Shareholders' equity: Stockholders' Equity Attributable to Parent [Abstract] Net assets acquired Noncash or Part Noncash Acquisition, Net Nonmonetary Assets Acquired (Liabilities Assumed) Document Fiscal Period Focus Document Fiscal Period Focus Other Comprehensive Income (Loss), Defined Benefit Plan, Gain (Loss), Reclassification Adjustment from AOCI, after Tax Other Comprehensive Income (Loss), Defined Benefit Plan, Gain (Loss), Reclassification Adjustment from AOCI, after Tax Loans and Leases Financing Receivable [Policy Text Block] Loans receivable Loans Receivable [Member] Redemption price (percent) Debt Instrument, Redemption Price, Percentage Entity Filer Category Entity Filer Category Common stock, par value $1 per share Common Stock Common Stock [Member] Product and Service [Domain] Product and Service [Domain] Preferred stock, $1 par value: 10,000,000 shares authorized; Series I, $25,000 per share liquidation preference; 4,000 and no shares issued and outstanding, respectively Preferred stock carrying amount Preferred Stock, Including Additional Paid in Capital, Net of Discount SBA/USDA guaranteed loans SBA USDA Guaranteed Loans [Member] SBA USDA Guaranteed Loans [Member] Allowance for credit losses - loans, Initial ACL - PCD loans Financing Receivable, Allowance for Credit Loss, Purchased with Credit Deterioration, Increase Financing Receivable, Allowance for Credit Loss [Table] Financing Receivable, Allowance for Credit Loss [Table] Schedule of reclassifications out of accumulated other comprehensive income Reclassification out of Accumulated Other Comprehensive Income [Table Text Block] Net Investment in Leases Net Investment in Lease [Abstract] Held-to-Maturity, Amortized Cost Debt Securities, Held-to-maturity, Maturity, Amortized Cost, Net [Abstract] Derivative liabilities Derivative Financial Instruments, Liabilities [Member] PCD loans: Financing Receivable, Purchased with Credit Deterioration, Amount at Purchase Price [Abstract] Modified Within the Previous Twelve Months that Have Subsequently Defaulted, Amortized Cost Financing Receivable, Troubled Debt Restructuring, Subsequent Default Interest Rate (percent) Debt Instrument, Interest Rate, Stated Percentage Southern Bancorp Capital Trust I Southern Bancorp Capital Trust One [Member] Represents information of Southern bancorp capital trust I. Loans and leases held for investment Total loans Total Financing Receivable, before Allowance for Credit Loss Exercises of stock options (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period Net change in cash and cash equivalents, including restricted cash Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents, Period Increase (Decrease), Including Exchange Rate Effect Minimum future lease payments expected to be received Sales-type and Direct Financing Leases, Lease Receivable, Fiscal Year Maturity [Abstract] Acquisitions Business Combination Disclosure [Text Block] Unrealized holding gains arising during period, Before-tax Amount OCI, Debt Securities, Available-for-Sale, Unrealized Holding Gain (Loss), before Adjustment and Tax Stated Maturity Date Debt Instruments Maturity Year This element represents debt instruments maturity year. Preferred stock dividends Dividends, Preferred Stock Stock Options Stock options Share-based Payment Arrangement, Option [Member] Recognized on hedged items Change in Unrealized Gain (Loss) on Hedged Item in Fair Value Hedge Nonaccrual loans with an allowance Financing Receivable, Nonaccrual, With Allowance Amount of financing receivable on nonaccrual status with an allowance for credit loss. Debt securities available for sale: Debt Securities, Available-for-sale [Abstract] Subsequent Events [Abstract] Subsequent Events [Abstract] Fair Value, Less than 12 Months Debt Securities, Held-to-maturity, Continuous Unrealized Loss Position, Less than 12 Months, Fair Value Number of available-for-sale debt securities in unrealized loss position Debt Securities, Available-for-sale, Unrealized Loss Position, Number of Positions Loan Restructuring Modification [Domain] Loan Restructuring Modification [Domain] Other-than-temporary impairment charges Other than Temporary Impairment Losses, Investments Held-to-Maturity, Fair Value, 1 to 5 years Debt Securities, Held-to-maturity, Maturity, Allocated and Single Maturity Date, Rolling after One Through Five Years, Fair Value Basis of Presentation and Consolidation Organization, Consolidation and Presentation of Financial Statements Disclosure [Text Block] Financing Receivable, Past Due [Line Items] Financing Receivable, Past Due [Line Items] Financing Receivable, Past Due [Line Items] Owner occupied commercial real estate Owner Occupied Commercial Real Estate [Member] Represents information of owner occupied commercial real estate. Capital surplus Additional Paid in Capital 2021 Finite-Lived Intangible Asset, Expected Amortization, Year One Total revenue Revenues Class of Stock [Axis] Class of Stock [Axis] Schedule of fair value of derivative financial instruments Schedule of Derivative Instruments [Table Text Block] Maturity date Debt Instrument, Maturity Date New Accounting Pronouncements or Change in Accounting Principle [Table] Accounting Standards Update and Change in Accounting Principle [Table] Unrealized holding losses on derivatives arising during the period, Tax (Expense) Benefit Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), before Reclassification, Tax Total liabilities Financial and Nonfinancial Liabilities, Fair Value Disclosure Residential mortgage Residential Mortgage [Member] Common stock issuable (in shares) Common Stock Issuable, Shares Represents number of shares of common stock issuable. Proceeds from issuance of Series I preferred stock, net of issuance costs Net proceeds from issuance of preferred stock Proceeds from Issuance of Preferred Stock and Preference Stock Diluted (in dollars per share) Earnings Per Share, Diluted Proceeds from sales Proceeds from sales Proceeds from Sale of Debt Securities, Available-for-sale Schedule of Stock by Class [Table] Schedule of Stock by Class [Table] Purchase price Financing Receivable, Purchased with Credit Deterioration, Amount at Purchase Price Common stock issued in acquisition Common stock issued (8,130,633 shares) Business Combination, Consideration Transferred, Equity Interests Issued and Issuable Acquisitions: Noncash or Part Noncash Acquisition, Net Nonmonetary Assets Acquired (Liabilities Assumed) [Abstract] Schedule of long-term debt Schedule of Long-term Debt Instruments [Table Text Block] Nonaccrual loans with no allowance Financing Receivable, Nonaccrual, No Allowance Entity Address, Address Line One Entity Address, Address Line One Prime Rate Prime Rate [Member] Entity Emerging Growth Company Entity Emerging Growth Company Supplemental consolidated pro forma revenue Business Acquisition, Pro Forma Revenue Deferred income tax expense Deferred Income Tax Expense (Benefit) Total capital Banking Regulation, Total Capital, Actual Investment securities, including tax exempt of $1,895, $1,118, $4,988 and $3,409, respectively Interest and Dividend Income, Securities, Operating Derivative financial instruments Total gross derivative instruments Derivative Liability, Fair Value, Gross Liability Accrued interest receivable Accrued Investment Income Receivable Fair Value Of Purchased Assets And Assumed Liabilities Recorded [Domain] Fair Value Of Purchased Assets And Assumed Liabilities Recorded [Domain] Represents information of purchased assets and assumed liabilities were recorded at their acquisition date fair values. Amortization of losses included in net income on available-for-sale securities transferred to held-to-maturity, Before-tax Amount Other Comprehensive Income, Reclassification Adjustment For Available For Sale Transferred To Held To Maturity Securities, Before Tax Other Comprehensive Income, Reclassification Adjustment For Available For Sale Transferred To Held To Maturity Securities, Before Tax Less: accumulated amortization Finite-Lived Intangible Assets, Accumulated Amortization ACL at acquisition Financing Receivable, Purchased with Credit Deterioration, Allowance for Credit Loss at Acquisition Date Tidelands Statutory Trust I Tidelands Statutory Trust One [Member] Represents information of Tidelands statutory trust one. Preferred stock authorized (in shares) Preferred Stock, Shares Authorized Loans held for sale at fair value Loans Held-for-sale, Fair Value Disclosure Common stock dividends Dividends, Common Stock, Cash Net cash flow hedge activity, Before-tax Amount Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), after Reclassification, before Tax Changes in balance of accretable yield for PCI loans Certain Loans Acquired in Transfer Accounted for as Debt Securities, Accretable Yield Movement Schedule [Roll Forward] Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] Schedule of Share-based Compensation Arrangements by Share-based Payment Award [Table] Schedule of Share-based Compensation Arrangements by Share-based Payment Award [Table] 2017 Financing Receivable, Year Four, Originated, Three Years before Current Fiscal Year Trading Symbol Trading Symbol Computation of basic and diluted earnings per share Weighted Average Number of Shares Outstanding Reconciliation [Abstract] Pledged as collateral to secure contingent funding sources Loans Pledged as Collateral Construction Construction Loans [Member] 2028 subordinated debentures Two Thousand Twenty Eight Subordinated Debentures [Member] Represents information of 2028 subordinated debentures. Weighted-Average Remaining Contractual Term (Years), Outstanding Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Outstanding, Weighted Average Remaining Contractual Terms Purchase accounting premium Sales Type And Direct Financing Leases, Purchase Accounting Premium Sales Type And Direct Financing Leases, Purchase Accounting Premium Interest-bearing deposits Interest-bearing Deposit Liabilities Entity Shell Company Entity Shell Company Fair Value Measurement Inputs and Valuation Techniques [Line Items] Fair Value Measurement Inputs and Valuation Techniques [Line Items] Recurring Fair Value, Recurring [Member] Mortgage loan gains and other related fees Mortgage Banking [Member] Expired (in dollars per share) Share-based Compensation Arrangements by Share-based Payment Award, Options, Expirations in Period, Weighted Average Exercise Price Probability of default rate Measurement Input, Default Rate [Member] Transfers into Level 3 Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Transfers Into Level 3 Document Type Document Type Revolvers converted to term loans Financing Receivable, Revolving, Converted to Term Loan Unsettled government guaranteed loan sales Unsettled Government Guaranteed Loan Sales Represents unsettled government guaranteed loan sale. Stock options granted (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross Total allowance for credit losses, Initial ACL - PCD loans Financing Receivable Allowance For Credit Loss And Off-Balance Sheet Credit Loss Liability, Purchased With Credit Deterioration, Increase Financing Receivable Allowance For Credit Loss And Off-Balance Sheet Credit Loss Liability, Purchased With Credit Deterioration, Increase Credit Loss Status [Domain] Credit Loss Status [Domain] Vested (in dollars per share) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period, Weighted Average Grant Date Fair Value 2022 Sales-Type and Direct Financing Leases, Lease Receivable, to be Received, Year Two Level 3 Fair Value, Inputs, Level 3 [Member] Derivative financial instruments Derivative Asset Residential mortgage-backed securities, Non-agency Residential Mortgage-Backed Securities, Issued By Private Enterprises [Member] Debt securities collateralized by residential real estate mortgage loans (mortgages), issued by non-governmental sponsored enterprises. Derivatives and Hedging Activities Derivative Instruments and Hedging Activities Disclosure [Text Block] Unrealized Loss, Less than 12 Months Debt Securities, Held-to-maturity, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss Average balances of impaired loans and income recognized on impaired loans Average Balances Of Impaired Loans And Income Recognized On Impaired Loans [Abstract] Unrealized gains on available-for-sale securities: OCI, Debt Securities, Available-for-Sale, Gain (Loss), after Adjustment and Tax [Abstract] Depositary shares, each representing 1/1000th interest in a share of Series I Non-Cumulative Preferred Stock Depositary share on Series I perpetual non-cumulative preferred stock Depositary Share On UCBI Series I Non-Cumulative Preferred Stock [Member] Depositary Share On UCBI Series I Non-Cumulative Preferred Stock Deposits in banks and short-term investments Federal Funds Sold Commercial Paper and Deposits In Banks Represents amount of federal funds sold, commercial paper and deposits in banks. Variable Rate [Axis] Variable Rate [Axis] Schedule of Business Acquisitions, by Acquisition [Table] Schedule of Business Acquisitions, by Acquisition [Table] Repurchase of common stock Payments for Repurchase of Common Stock Plan vesting period Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period Bifurcated embedded derivatives Bifurcated Embedded Derivative [Member] Represents the bifurcated embedded derivatives. Available-for-Sale, Amortized Cost, 5 to 10 years Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, Rolling after Five Through Ten Years, Amortized Cost Entity Address, State or Province Entity Address, State or Province Vested (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period Financial Asset, Period Past Due [Axis] Financial Asset, Period Past Due [Axis] Retained earnings Retained Earnings (Accumulated Deficit) 2030 senior debentures Two Thousand Thirty Senior Debentures [Member] Two Thousand Thirty Senior Debentures Right-of-use asset Operating Lease, Right-of-Use Asset Less discount Debt Instrument, Unamortized Discount Derivative assets Derivative Financial Instruments, Assets [Member] Total deposits Deposits Schedule of assets measured at fair value on a recurring basis using significant unobservable inputs Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Table Text Block] Loans Past Due - Accruing and Nonaccrual Financing Receivable Recorded Investment, Past Due, Accruing And Nonaccrual Financing Receivable Recorded Investment, Past Due, Accruing And Nonaccrual Premises and equipment, net Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Property, Plant, and Equipment Customer derivative positions Customer Swap Position [Member] Represents the customer swap positions. Allowance for credit losses, Individually evaluated for impairment Financing Receivable, Allowance for Credit Losses, Individually Evaluated for Impairment Held-to-Maturity, Amortized Cost, 5 to 10 years Debt Securities, Held-to-Maturity, Amortized Cost, Maturity, Allocated and Single Maturity Date, after Year 5 Through 10 Amortization of prior service cost and actuarial losses included in net periodic pension cost for defined benefit pension plan, Before-tax Amount Other Comprehensive Income Loss Amortization Of Prior Service Cost And Actuarial Losses Included In Net Periodic Pension Cost For Defined Benefit Pension Plan Before Tax Amount Represents amount of other comprehensive income (loss) amortization of prior service cost and actuarial losses included in net periodic pension cost for defined benefit pension plan, before tax amount. Additions Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Issuances Fair Value by Liability Class [Domain] Fair Value by Liability Class [Domain] Hedging Designation [Domain] Hedging Designation [Domain] U.S. Government agencies US Treasury and Government [Member] Total lease cost Lease, Cost Exercisable (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Number Servicing rights for SBA/USDA loans, measurement input Servicing Asset, Measurement Input Other investing activities, net Payments for (Proceeds from) Other Investing Activities Liability Class [Axis] Liability Class [Axis] Amortization of restricted stock unit awards APIC, Share-based Payment Arrangement, Increase for Cost Recognition Adjusted Balance Cumulative Effect, Period of Adoption, Adjusted Balance [Member] Unpaid Principal Balance, With no related allowance recorded Impaired Financing Receivable, with No Related Allowance, Unpaid Principal Balance Employees Employee [Member] Employee Loan Restructuring Modification [Axis] Loan Restructuring Modification [Axis] Business Acquisition [Axis] Business Acquisition [Axis] Gross Unrealized Losses Debt Securities, Held-to-maturity, Accumulated Unrecognized Loss Financing Receivable Portfolio Segment [Axis] Financing Receivable Portfolio Segment [Axis] Common stock issued for acquisitions (in shares) Stock Issued During Period, Shares, Acquisitions Held-to-Maturity, Fair Value, Within 1 year Debt Securities, Held-to-maturity, Maturity, Allocated and Single Maturity Date, Rolling within One Year, Fair Value Forecast Forecast [Member] Commercial mortgage-backed, Agency Commercial Mortgage-Backed Securities, Issued By US Government Sponsored Enterprises [Member] Debt securities collateralized by commercial real estate mortgage loans (mortgages), issued by US Government Sponsored Enterprises, such as Federal Home Loan Mortgage Corporation (FHLMC or Freddie Mac). Net income per common share: Earnings Per Share, Basic and Diluted [Abstract] Amortization of losses included in net income on terminated derivative financial instruments that were previously accounted for as cash flow hedges, Tax (Expense) Benefit Other Comprehensive Income Loss Amortization Of Losses Included In Net Income On Terminated Derivative Financial Instruments Which Previously Accounted For As Cash Flow Hedges Tax Represents the amount of tax expense (benefit) related to amortization of losses included in net income on terminated derivative financial instruments that were previously accounted for as cash flow hedges. Merger-related and other charges Merger-related costs excluded from pro forma Merger-related and other charges Business Combination, Acquisition Related Costs Total capital, Well Capitalized Banking Regulation, Total Risk-Based Capital Ratio, Well Capitalized, Minimum Allowance for credit losses, PCI Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Allowance for Loan Losses Schedule of loans by aging category and accrual status Financing Receivable, Past Due [Table Text Block] Liabilities Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Liabilities [Abstract] Net income (expense) recognized on cash flow hedges Gain (Loss) On Cash Flow Hedges Recognized In Earnings Gain (Loss) On Cash Flow Hedges Recognized In Earnings Preferred stock issued (in shares) Preferred Stock, Shares Issued Derivatives not designated as hedging instruments Interest Rate Derivative Instruments Not Designated as Hedging Instruments, Asset at Fair Value U.S. Government agencies US Government Agencies Debt Securities [Member] Deferred compensation plan liability Deferred Compensation Liability, Current and Noncurrent As Recorded By Three Shores As Recorded By Three Shores [Member] As Recorded By Three Shores Schedule of risk category of loans by vintage year or class of loans Financing Receivable Credit Quality Indicators [Table Text Block] Tier 1 capital, Well Capitalized Banking Regulation, Tier One Risk-Based Capital Ratio, Well Capitalized, Minimum Business Combinations [Abstract] Business Combinations [Abstract] Actual net income (loss) included since acquisition date Business Combination, Pro Forma Information, Earnings or Loss of Acquiree since Acquisition Date, Actual Residential mortgage servicing rights Residential Mortgage Servicing Asset At Fair Value, Amount Residential Mortgage Servicing Asset At Fair Value, Amount Future minimum lease payments Lessee, Operating Lease, Liability, Payment, Due [Abstract] Commercial Commercial Portfolio Segment [Member] Increase (Decrease) in Stockholders' Equity [Roll Forward] Increase (Decrease) in Stockholders' Equity [Roll Forward] Weighted-Average Remaining Contractual Term (Years), Exercisable Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Weighted Average Remaining Contractual Term Other Other Type Of Modification [Member] Represents type of modification other not defined elsewhere. Dealer offsets to bifurcated embedded derivatives Dealer Offsets To Bifurcated Embedded Derivatives [Member] Represents the dealer offsets to bifurcated embedded derivatives. Goodwill [Roll Forward] Goodwill [Roll Forward] Financial Asset, Period Past Due [Domain] Financial Asset, Period Past Due [Domain] Schedule of computation of basic and diluted earnings per share Schedule of Earnings Per Share, Basic and Diluted [Table Text Block] Reconciliation of Assets at Level 3 Measurement Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] Effect of dilutive securities Dilutive Securities, Effect on Basic Earnings Per Share [Abstract] Fair Value Of Purchased Assets And Assumed Liabilities Recorded [Axis] Fair Value Of Purchased Assets And Assumed Liabilities Recorded [Axis] Represents purchased assets and assumed liabilities were recorded at their acquisition date fair values. Schedule of purchased assets and assumed liabilities Schedule of Recognized Identified Assets Acquired and Liabilities Assumed [Table Text Block] Other Comprehensive (Income) Loss, Defined Benefit Plan, after Reclassification Adjustment, Tax Other Comprehensive (Income) Loss, Defined Benefit Plan, after Reclassification Adjustment, Tax Balance at beginning of period Balance at end of period Certain Loans Acquired in Transfer Accounted for as Debt Securities, Accretable Yield Amortization of losses included in net income on terminated derivative financial instruments that were previously accounted for as cash flow hedges, Net of Tax Amount Other Comprehensive Income Loss Amortization Of Losses Included In Net Income On Terminated Derivative Financial Instruments Which Previously Accounted For As Cash Flow Hedges Net Of Tax Represents the amount after tax related to amortization of losses included in net income on terminated derivative financial instruments that were previously accounted for as cash flow hedges. Net cash provided by operating activities Net Cash Provided by (Used in) Operating Activities Nonaccrual Loans Nonaccrual loans Financing Receivable, Nonaccrual Entity Central Index Key Entity Central Index Key Reclassifications related to derivative financial instruments accounted for as cash flow hedges Accumulated Gain (Loss), Net, Cash Flow Hedge, Parent [Member] Derivative Instrument [Axis] Derivative Instrument [Axis] Finite-Lived Intangible Assets by Major Class [Axis] Finite-Lived Intangible Assets by Major Class [Axis] Financing Receivable, Past Due [Table] Financing Receivable, Past Due [Table] Senior debentures Senior Notes [Member] Mortgage banking derivatives Mortgage Banking Derivatives [Member] Information of Mortgage banking derivatives. Derivative instruments designated as cash flow hedges: Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), after Reclassification and Tax [Abstract] Consumer Consumer Portfolio Segment [Member] Amortized Cost Debt Securities, Available-for-sale, Amortized Cost Fair value Business Combination, Acquired Receivable, Fair Value Gross Unrealized Gains Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax Statement of Cash Flows [Abstract] Statement of Cash Flows [Abstract] Accrued interest receivable Business Combination, Recognized Identifiable Assets Acquired And Liabilities Assumed, Current Assets, Accrued Interest Receivables Business Combination, Recognized Identifiable Assets Acquired And Liabilities Assumed, Current Assets, Accrued Interest Receivables Supplemental consolidated pro forma net income (loss) Business Acquisition, Pro Forma Net Income (Loss) Hedge Accounting Basis Adjustment Hedged Liability, Fair Value Hedge, Cumulative Increase (Decrease) Amounts included in earnings - fair value adjustments Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Earnings Entity Listings [Table] Entity Listings [Table] Income Statement Location [Axis] Income Statement Location [Axis] Entity Common Stock, Shares Outstanding Entity Common Stock, Shares Outstanding Noninterest income: Noninterest Income [Abstract] Losses to be reclassified from accumulated other comprehensive income into earnings over the next twelve months Interest Rate Cash Flow Hedge Gain (Loss) to be Reclassified During Next 12 Months, Net Gross contractual amounts receivable Business Combination, Acquired Receivables, Gross Contractual Amount Aggregate notional amount Derivative, Notional Amount Amortization of intangibles Amortization of Intangible Assets Cash and cash equivalents Cash, Cash Equivalents, and Federal Funds Sold Vesting of restricted stock, net of shares surrendered to cover payroll taxes, shares deferred (in shares) Vesting Of Restricted Stock Shares Deferred This element represents value of common stock issued to dividend reinvestment plan and employee benefit plans. Derivative assets - customer derivative positions Derivative Assets Customer Derivative Positions [Member] Derivative Assets Customer Derivative Positions Estimated residual value of leased equipment Sales Type And Direct Financing Leases, Unguaranteed Residual Asset Sales Type And Direct Financing Leases, Unguaranteed Residual Asset Prepayment rate Measurement Input, Prepayment Rate [Member] Issuance of stock Stock Issued During Period, Value, New Issues Termination of defined benefit pension plan Accumulated Defined Benefit Plans Adjustment Net Loss On Plan Termination [Member] Accumulated Defined Benefit Plans Adjustment Net Loss On Plan Termination Vesting of restricted stock, net of shares surrendered to cover payroll taxes, shares issued (in shares) Stock Issued During Period, Shares, Restricted Stock Award, Net of Forfeitures Schedule of right-of-use asset and operating lease liability Schedule Of Operating Lease Right Of Use Assets And Lease Liabilities [Table Text Block] Schedule Of Operating Lease Right Of Use Assets And Lease Liabilities Gains from sales of other loans, net Gain (Loss) on Sales of Loans, Net Scenario [Axis] Scenario [Axis] Loans Past Due Financing Receivable, 90 Days or More Past Due, Still Accruing Leverage ratio Banking Regulation, Tier One Leverage Capital Ratio, Actual Title of 12(b) Security Title of 12(b) Security Earliest Call Date Debt Instrument Earliest Call Year This element represents debt instrument earliest call year. Net core deposit intangible Finite-Lived Intangible Assets, Net Schedule of additional information related to acquired loan portfolio Additional Information Related To Acquired Loan [Table Text Block] Tabular disclosure of the amounts recognized as additional information related to the acquired loan. Rate Reduction Contractual Interest Rate Reduction [Member] Unrealized holding gains arising during period, Net of Tax Amount OCI, Debt Securities, Available-for-Sale, Unrealized Holding Gain (Loss), before Adjustment, after Tax Debt securities available-for-sale and equity securities: Debt Securities Available-For-Sale And Equity Securities [Abstract] Debt Securities Available-For-Sale And Equity Securities [Abstract] Unrealized holding gains arising during period, Tax (Expense) Benefit OCI, Debt Securities, Available-for-Sale, Unrealized Holding Gain (Loss), before Adjustment, Tax Total interest expense Interest expense Interest Expense Allowance for unfunded commitments, (Release) Provision Off-Balance Sheet, Credit Loss, Liability, Credit Loss Expense (Reversal) Servicing rights for SBA/USDA loans SBA Servicing Rights [Member] Represents SBA servicing rights. Summary of available for sale securities in an unrealized loss position Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss [Abstract] Product and Service [Axis] Product and Service [Axis] Recognized on derivatives Change in Unrealized Gain (Loss) on Fair Value Hedging Instruments Other Noninterest Income, Other Operating Income Prior service cost Accumulated Defined Benefit Plans Adjustment, Net Prior Service Attributable to Parent [Member] Premium amortization expense excluded from assessment of hedge effectiveness Loss from Components Excluded from Assessment of Cash Flow Hedge Effectiveness Proceeds from FHLB advances Proceeds from FHLBank Borrowings, Financing Activities Recognition period for unrecognized compensation expense Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition Income producing commercial real estate Income Producing Commercial Real Estate [Member] Property that represents income producing commercial real estate. Allowance for Credit Loss Financing Receivable, Allowance for Credit Loss [Roll Forward] Net income available to common shareholders Net income available to common shareholders Net Income (Loss) Available to Common Stockholders, Basic Unrealized holding losses on derivatives arising during the period, Before-tax Amount Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), before Reclassification and Tax Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] Available-for-Sale, Fair Value Debt Securities, Available-for-sale, Maturity, Fair Value, Rolling Maturity [Abstract] Fair Value, Recurring and Nonrecurring [Table] Fair Value, Recurring and Nonrecurring [Table] Less allowance for credit losses - loans and leases Increase in ACL for loans Less allowance for credit losses - loans Allowance for credit losses - loans, Beginning Balance Allowance for credit losses - loans, Ending Balance Allowance for credit losses, Ending balance Financing Receivable, Allowance for Credit Loss Less: Amounts subject to master netting agreements Derivative Asset, Not Offset, Policy Election Deduction Aggregate Intrinsic Value, Outstanding Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Aggregate Intrinsic Value, Outstanding Assets acquired Noncash or Part Noncash Acquisition, Value of Assets Acquired Gross gains on sales Debt Securities, Available-for-sale, Realized Gain Transfers of loans to foreclosed properties Real Estate Owned, Transfer to Real Estate Owned Debt Instrument [Axis] Debt Instrument [Axis] Fair value hedging of interest rate risk Fair value hedging Fair Value Hedging [Member] Short-term borrowings Interest Expense, Other Short-term Borrowings Antidilutive Securities, Name [Domain] Antidilutive Securities, Name [Domain] Gross additional interest revenue that would have been earned if the nonaccrual loans had performed as per original terms Loans and Leases Receivable, Impaired, Interest Lost on Nonaccrual Loans Class of Stock [Line Items] Class of Stock [Line Items] Derivative financial instruments Derivative Liability Trust preferred securities Trust Preferred Securities [Member] Represents information of trust preferred securities. Fair value hedge Fair Value Hedge Liabilities Variable lease cost Variable Lease, Cost Derivative asset and liabilities, measurement input Derivative Asset (Liability) Net, Measurement Input Entity Listings [Line Items] Entity Listings [Line Items] Minimum future lease payments receivable Sales-type and Direct Financing Leases, Lease Receivable Adjustments to reconcile net income to net cash provided by operating activities: Adjustments, Noncash Items, to Reconcile Net Income (Loss) to Cash Provided by (Used in) Operating Activities [Abstract] Modified Within the Previous Twelve Months that Have Subsequently Defaulted, Number of Contracts Financing Receivable, Troubled Debt Restructuring, Subsequent Default, Number of Contracts Subsequent Event Subsequent Event [Member] Held-to-Maturity, Fair Value Debt Securities, Held-to-maturity, Maturity, Fair Value, Rolling Maturity [Abstract] Schedule of available-for-sale securities sales activity Schedule of Realized Gain (Loss) [Table Text Block] Schedule of loans individually evaluated for impairment under Incurred Loss by class Impaired Financing Receivables [Table Text Block] Total capital, Minimum Banking Regulation, Total Risk-Based Capital Ratio, Capital Adequacy, Minimum Noninterest-bearing demand Noninterest-bearing Deposit Liabilities Lending and loan servicing expense Loan Portfolio Expense Available-for-Sale, Amortized Cost, Within 1 year Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, Rolling within One Year, Amortized Cost Fair Value Estimate of Fair Value Measurement [Member] Derivative assets - mortgage Derivative Assets Mortgage [Member] Derivative Assets Mortgage 2024 Finite-Lived Intangible Asset, Expected Amortization, Year Four Occupancy Occupancy, Net Core deposit intangible acquired Core deposit intangible Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Finite-Lived Intangibles Increase reclassified from amortized cost basis of PCD financial assets previously classified as PCI Financing Receivable, Change in Method, Credit Loss Expense (Reversal) Less: Cash collateral received/pledged Derivative Liability, Fair Value of Collateral TDRs Financing Receivable, Troubled Debt Restructuring Goodwill expected to be tax deductible Business Acquisition, Goodwill, Expected Tax Deductible Amount Repurchase program remaining authorization Stock Repurchase Program, Remaining Authorized Repurchase Amount Residential mortgage-backed securities Residential Mortgage Backed Securities [Member] Financing Receivable, Allowance for Credit Loss [Line Items] Financing Receivable, Allowance for Credit Loss [Line Items] Financing Receivable, Allowance for Credit Loss [Line Items] Goodwill, gross, beginning of period Goodwill, gross, end of period Goodwill, Gross Comprehensive income, Net of Tax Amount Comprehensive Income (Loss), Net of Tax, Attributable to Parent Preferred stock, par value (in dollars per share) Preferred Stock, Par or Stated Value Per Share Not designated as hedging instrument, economic hedge Not Designated as Hedging Instrument, Economic Hedge [Member] Net unrealized gains, Net of Tax Amount Other Comprehensive Income Loss Unrealized Holding Gain Loss On Securities Net Of Reclassification and Valuation Allowance Arising During Period Net Of Tax Other comprehensive income loss unrealized holding gain loss on securities net of reclassification and valuation allowance arising during period net of tax. Debt securities held to maturity: Debt Securities, Held-to-maturity, Fair Value to Amortized Cost [Abstract] Legal Entity [Axis] Legal Entity [Axis] City Area Code City Area Code Document Period End Date Document Period End Date Preferred stock redemption price (in dollars per share) Preferred Stock, Redemption Price Per Share Repurchase program authorized amount Stock Repurchase Program, Authorized Amount Unearned income Sales Type And Direct Financing Leases, Deferred Selling Profit Sales Type And Direct Financing Leases, Deferred Selling Profit Schedule of Held-to-maturity Securities [Line Items] Schedule of Held-to-maturity Securities [Line Items] Tier 1 capital Banking Regulation, Tier One Risk-Based Capital Ratio, Actual 2027 senior debentures Two Thousand Twenty Seven Senior Debentures [Member] Represents information of 2027 senior debentures. Long-term Debt, Type [Domain] Long-term Debt, Type [Domain] Dealer offsets to customer derivative positions Dealer Offset To Customer Swap Position [Member] Represents the dealer offset to customer swap position. Proceeds from maturities and calls Proceeds from Maturities, Prepayments and Calls of Held-to-maturity Securities Stock based compensation Share-based Payment Arrangement, Noncash Expense Series I perpetual non-cumulative preferred stock UCBI Series I Non-Cumulative Preferred Stock [Member] UCBI Series I Non-Cumulative Preferred Stock Cover [Abstract] Cover [Abstract] Measurement Input Type [Axis] Measurement Input Type [Axis] Purchases of common stock (in shares) Shares repurchased (in shares) Stock Repurchased and Retired During Period, Shares Derivative Instruments, Gain (Loss) [Table] Derivative Instruments, Gain (Loss) [Table] Proceeds from issuance of common stock for dividend reinvestment and employee benefit plans Proceeds From Issuance Of Common Stock For Dividend Reinvestment and Employee Benefit Plans Represents amount of cash inflow from the amount received from the stock plan and capital contributions to an entity associated with a dividend reinvestment plan during the period. Long-term debt Total long-term debt Long-term Debt Operating Leases Lessee, Operating Leases [Text Block] Balance at beginning of period Balance at end of period Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value Operating Lease Income and Expense Lease, Cost [Abstract] Reclassification adjustment for losses included in net income, Net of Tax Amount Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI for Sale of Securities, Net of Tax Equity Components [Axis] Equity Components [Axis] Net cash flow hedge activity, Net of tax Amount Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), after Reclassification and Tax Allocated allowance for TDRs Specific Reserves Allocated To Customers Whose Loan Terms Modified In Troubled Debt Restructurings This element represents specific reserves allocated to customers whose loan terms modified in troubled debt restructurings. Liabilities assumed Noncash or Part Noncash Acquisition, Value of Liabilities Assumed Total noninterest income Noninterest Income Debt Instrument, Name [Domain] Debt Instrument, Name [Domain] Available-for-Sale, Amortized Cost, 1 to 5 years Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, Rolling after One Through Five Years, Amortized Cost Receivables [Abstract] Receivables [Abstract] Balance Sheet Location [Domain] Balance Sheet Location [Domain] Assets acquired Total assets acquired Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Assets Asset-backed securities Asset-backed Securities [Member] Entity Interactive Data Current Entity Interactive Data Current Loss given default rate Measurement Input, Loss Given Default [Member] Measurement Input, Loss Given Default Weighted average exercise price of stock options (in dollars per share) Share-based Compensation Arrangements by Share-based Payment Award, Options, Exercises in Period, Weighted Average Exercise Price Operating activities: Net Cash Provided by (Used in) Operating Activities [Abstract] Common and Preferred Stock Stockholders' Equity Note Disclosure [Text Block] Allowance for credit losses - loans, Recoveries Financing Receivable, Allowance for Credit Loss, Recovery Schedule of stock option activity Share-based Payment Arrangement, Option, Activity [Table Text Block] Schedule of debt securities available for sale in an unrealized loss position Debt Securities, Available-for-sale, Unrealized Loss Position, Fair Value [Table Text Block] Proceeds from maturities and calls Proceeds from Maturities, Prepayments and Calls of Debt Securities, Available-for-sale Debt securities held to maturity, fair value Fair value Securities held-to-maturity Debt Securities, Held-to-maturity, Fair Value Remainder of 2020 Finite-Lived Intangible Asset, Expected Amortization, Remainder of Fiscal Year Common stock issuable: 590,521 and 664,640 shares, respectively Common Stocks Issuable Represents amount of carrying amount of common stock issuable. Unpaid Principal Balance Impaired Financing Receivable, Unpaid Principal Balance Derivative Assets Derivative Asset [Member] Represents Derivative Asset. Earliest redemption date Debt Instrument, Call Date, Earliest Derivative [Table] Derivative [Table] Statement of Stockholders' Equity [Abstract] Statement of Stockholders' Equity [Abstract] Derivatives not designated as hedging instruments Interest Rate Derivative Instruments Not Designated as Hedging Instruments, Liability at Fair Value Revolvers Financing Receivable, Revolving Recorded Investment Impaired Financing Receivable, Recorded Investment [Abstract] Proceeds from sales of premises and equipment Proceeds from Sale of Property, Plant, and Equipment Core deposit intangible Intangible Assets, Gross (Excluding Goodwill) Total noninterest expenses Noninterest Expense Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items] Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items] Recorded Investment Impaired Financing Receivable, Recorded Investment Not designated as hedging instrument Not Designated as Hedging Instrument [Member] Carrying value of securities pledged to secure public deposits, derivatives and other secured borrowings Pledged Financial Instruments, Not Separately Reported, Securities Total Lessee, Operating Lease, Liability, to be Paid Non-credit discount Financing Receivable, Purchased with Credit Deterioration, Discount (Premium) Debt Security Category [Domain] Other than Temporary Impairment, Credit Losses Recognized in Earnings, Categories of Investments [Domain] Sublease income and rental income from owned properties under operating leases Operating Lease, Lease Income Classifications of loans Financing Receivable, after Allowance for Credit Loss [Abstract] Loans Past Due, 30 - 59 Days Financial Asset, 30 to 59 Days Past Due [Member] Dividend payable date Dividends Payable, Date to be Paid Indirect auto Automobile Loan [Member] Securities gains (losses), net Net gains (losses) on sales of securities Securities gains (losses), net Debt Securities, Available-for-sale, Realized Gain (Loss) Communications and equipment Communications and Information Technology Fair Value Measurement Inputs and Valuation Techniques [Table] Fair Value Measurement Inputs and Valuation Techniques [Table] Financing Receivable, Impaired [Line Items] Financing Receivable, Impaired [Line Items] Document Transition Report Document Transition Report Title of Individual [Axis] Title of Individual [Axis] Unrealized Loss, 12 Months or More Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss Interest Revenue Recognized During Impairment Impaired Financing Receivable, Interest Income, Accrual Method Other liabilities Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Noncurrent Liabilities, Other Derivative financial instruments Total gross derivative instruments Derivative Asset, Fair Value, Gross Asset Level 2 Fair Value, Inputs, Level 2 [Member] Schedule of presentation of assets measured at fair value on nonrecurring basis Fair Value Measurements, Nonrecurring [Table Text Block] Prior Financing Receivable, Originated, More than Five Years before Current Fiscal Year Document Quarterly Report Document Quarterly Report Liabilities: Liabilities, Fair Value Disclosure [Abstract] Financing Receivable, Troubled Debt Restructuring [Table] Financing Receivable, Troubled Debt Restructuring [Table] Total other comprehensive income, Before-tax Amount Other Comprehensive Income (Loss), before Tax, Portion Attributable to Parent Changes in expected cash flows that do not affect nonaccretable difference Changes In Expected Cash Flows That Do Not Affect Nonaccretable Difference Represents changes in expected cash flows that do not affect nonaccretable difference. ASC 326 Accounting Standards Update 2016-13 [Member] Subsequent Event [Line Items] Subsequent Event [Line Items] Cumulative Effect, Period of Adoption [Axis] Cumulative Effect, Period of Adoption [Axis] Purchased loans Financial Asset Acquired with Credit Deterioration [Member] Accounting Standards Updates and Recently Adopted Standards Accounting Standards Update and Change in Accounting Principle [Text Block] PPP loans included in commercial & industrial Commercial And Industrial Classification, PPP Loan Component [Member] Commercial And Industrial Classification, PPP Loan Component Basic (in dollars per share) Earnings Per Share, Basic Entity File Number Entity File Number Expired (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Options, Expirations in Period Operating lease, weighted average remaining lease term (in years) Operating Lease, Weighted Average Remaining Lease Term Net amount Derivative Asset, Fair Value, Offset Against Collateral, Net of Not Subject to Master Netting Arrangement, Policy Election Assets Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Assets [Abstract] Allowance for unfunded commitments, Individually evaluated for impairment Off-Balance Sheet Liability, Credit Loss Liability, Individually Evaluated For Impairment Off-Balance Sheet Liability, Credit Loss Liability, Individually Evaluated For Impairment Federal Home Loan Bank advances Interest Expense, Federal Home Loan Bank and Federal Reserve Bank Advances, Short-term Schedule of changes in the balance of the accretable yield for PCI loans Schedule Of Changes In Value Of Accretable Yield For Acquired Loans [Table Text Block] Tabular disclosure of changes in value of accretable yield for acquired loans. Compensation expense Share-based Payment Arrangement, Expense Realized gains (losses) on available-for-sale securities AOCI, Accumulated Gain (Loss), Debt Securities, Available-for-sale, Parent [Member] Balance Sheet Location [Axis] Balance Sheet Location [Axis] Goodwill and Intangible Assets Disclosure [Abstract] Goodwill and Intangible Assets Disclosure [Abstract] Amortization of losses included in net income on terminated derivative financial instruments that were previously accounted for as cash flow hedges, Before-tax Amount Other Comprehensive Income Loss Amortization Of Losses Included In Net Income On Terminated Derivative Financial Instruments Which Previously Accounted For As Cash Flow Hedges Before Tax Represents the amount before tax related to amortization of losses included in net income on terminated derivative financial instruments that were previously accounted for as cash flow hedges. Aggregate Intrinsic Value, Exercisable Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Intrinsic Value Income tax benefit related to expense for share-based awards Share-based Payment Arrangement, Expense, Tax Benefit Deferred compensation plan assets Deferred Compensation Plan Assets Schedule of major classifications of loan and lease portfolio Schedule of Accounts, Notes, Loans and Financing Receivable [Table Text Block] Deposits Deposits, Fair Value Disclosure Professional fees Professional Fees Receivable [Domain] Receivable [Domain] Subsequent Event [Table] Subsequent Event [Table] Proceeds from sale of other real estate Proceeds from Sale of Other Real Estate Common stock issued from deferred compensation plan, net of shares surrendered to cover payroll taxes (in shares) Shares Issued, Shares, Share-based Payment Arrangement, after Forfeiture Schedule of Long-term Debt Instruments [Table] Schedule of Long-term Debt Instruments [Table] Total identifiable net assets Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Net Granted (in dollars per share) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value Residential mortgage servicing rights, measurement input Residential Mortgage Servicing Asset Measurement Input Residential Mortgage Servicing Asset, Measurement Input Investing activities: Net Cash Provided by (Used in) Investing Activities [Abstract] Available-for-Sale, Fair Value, Within 1 year Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, Rolling within One Year, Fair Value Brokerage and wealth management fees Brokerage Commissions Revenue Number of banking offices Number Of Branches Represents number of branches operated by entity. Schedule of contractual amount of off-balance sheet instruments Schedule of Fair Value, Off-balance Sheet Risks [Table Text Block] Service charges and other related fees Noninterest Income, Other Interest expense Interest Expense [Member] Cash flow hedge Interest Rate Cash Flow Hedge Liability at Fair Value Cash and due from banks Cash and Due from Banks Statement of Comprehensive Income [Abstract] Statement of Comprehensive Income [Abstract] Net income (expense) recognized on fair value hedges Gain (Loss) on Fair Value Hedges Recognized in Earnings Total liabilities and shareholders' equity Liabilities and Equity Mortgage loan gains and other related fees Fair Value, Option, Changes in Fair Value, Gain (Loss) Accumulated other comprehensive income Accumulated Other Comprehensive Income (Loss), Net of Tax Net cash flow hedge activity, Tax (Expense) Benefit Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), after Reclassification, Tax Portion at Fair Value Measurement [Member] Portion at Fair Value Measurement [Member] Schedule of cost basis, unrealized gains and losses and fair value of debt securities held to maturity Debt Securities, Held-to-maturity [Table Text Block] Operating lease cost Operating Lease, Cost Liabilities assumed Total liabilities assumed Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Liabilities Hedging Relationship [Axis] Hedging Relationship [Axis] Loans and leases, net Amount of loans Financing Receivable, after Allowance for Credit Loss Antidilutive securities excluded from computation (in shares) Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount FHLB advances and long-term debt Business Combination, Recognized Identifiable Assets Acquired And Liabilities Assumed, Long Term Debt And Federal Home Loan Bank Advances Business Combination, Recognized Identifiable Assets Acquired And Liabilities Assumed, Long Term Debt And Federal Home Loan Bank Advances Held-to-Maturity, Fair Value, More than 10 years Debt Securities, Held-to-maturity, Maturity, Allocated and Single Maturity Date, Rolling after 10 Years, Fair Value Equity Component [Domain] Equity Component [Domain] Premises and equipment, net Property, Plant and Equipment, Net Gains (losses) on active cash flow hedging relationships: Effect of Cash Flow Hedges on Results of Operations [Abstract] Less: Cash collateral received/pledged Derivative Asset, Fair Value of Collateral Entity Tax Identification Number Entity Tax Identification Number Lessee, Lease, Description [Table] Lessee, Lease, Description [Table] Watch Watch [Member] Represents watch. Stock-Based Compensation Share-based Payment Arrangement [Text Block] Net income Net income, Net of Tax Amount Net income Net Income (Loss) Attributable to Parent Changes in assets and liabilities: Increase (Decrease) in Operating Capital [Abstract] LIBOR London Interbank Offered Rate (LIBOR) [Member] Allowance for credit losses - loans, (Release) Provision Financing Receivable, Credit Loss, Expense (Reversal) Debt Securities, Trading, and Equity Securities, FV-NI [Table] Debt Securities, Trading, and Equity Securities, FV-NI [Table] Current Fiscal Year End Date Current Fiscal Year End Date Noninterest expenses: Operating Expenses [Abstract] Gross Unrealized Gains Debt Securities, Held-to-maturity, Accumulated Unrecognized Gain Risk participations Risk Participations [Member] Represents information about risk participations. Structure Extended Maturity [Member] Debt securities held-to-maturity (fair value $413,820 and $287,904, respectively) Amortized Cost Debt Securities, Held-to-maturity Other Comprehensive (Income) Loss, Defined Benefit Plan, before Tax, after Reclassification Adjustment, Attributable to Parent Other Comprehensive (Income) Loss, Defined Benefit Plan, before Tax, after Reclassification Adjustment, Attributable to Parent Shares Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward] Loans and leases, net Loans Receivable, Fair Value Disclosure Derivatives designated as hedging instruments Derivative Instruments in Hedges, Assets, at Fair Value Liabilities: Financial Instruments, Financial Liabilities, Balance Sheet Groupings [Abstract] Allowance for credit losses, Collectively evaluated for impairment Financing Receivable, Allowance for Credit Losses, Collectively Evaluated for Impairment Financing Receivable, Credit Quality Indicator [Table] Financing Receivable, Credit Quality Indicator [Table] Other Comprehensive (Income) Loss, Defined Benefit Plan, after Tax and Reclassification Adjustment, Attributable to Parent Other Comprehensive (Income) Loss, Defined Benefit Plan, after Tax and Reclassification Adjustment, Attributable to Parent Aggregate Intrinsic Value, Vested Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Aggregate Intrinsic Value, Vested 2020 Financing Receivable, Year One, Originated, Current Fiscal Year Supplemental disclosures of cash flow information: Supplemental Cash Flow Information [Abstract] Business Acquisition, Acquiree [Domain] Business Acquisition, Acquiree [Domain] Financial instruments Unused Commitments to Extend Credit Commitments to lend additional amounts to customers with outstanding loans classified as TDRs Financing Receivable, Troubled Debt Restructuring, Commitment to Lend Leverage ratio, Well Capitalized Banking Regulation, Tier One Leverage Capital Ratio, Well Capitalized, Minimum Transfers into Level 3 Fair Value, Measurement with Unobservable Inputs Reconciliation, Liability, Transfers Into Level 3 Commercial mortgage-backed, Non-agency Commercial Mortgage-Backed Securities, Issued By Private Enterprises [Member] Debt securities collateralized by commercial real estate mortgage loans (mortgages), issued by non-governmental sponsored enterprises. Derivative assets Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Assets, Bank Owned Life Insurance Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Assets, Bank Owned Life Insurance Increase in ACL for unfunded commitments Allowance for unfunded commitments, Beginning Balance Allowance for unfunded commitments, Ending Balance Allowance for unfunded commitments, Ending Balance Off-Balance Sheet, Credit Loss, Liability Other comprehensive income Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Liability, Gain (Loss) Included in Other Comprehensive Income (Loss) Three Shores Three Shores Bancorporation, Inc. [Member] Three Shores Bancorporation, Inc. Leverage ratio, Minimum Banking Regulation, Tier One Leverage Capital Ratio, Capital Adequacy, Minimum Preferred stock dividend rate (percent) Preferred Stock, Dividend Rate, Percentage Reclassification out of Accumulated Other Comprehensive Income [Table] Reclassification out of Accumulated Other Comprehensive Income [Table] U.S. Treasuries US Treasury Securities [Member] Issuance of stock (in shares) Stock Issued During Period, Shares, New Issues Available-for-Sale, Fair Value, 5 to 10 years Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, Rolling after Five Through Ten Years, Fair Value Unrealized Loss, Less than 12 Months Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss Amortization of prior service cost and actuarial losses included in net periodic pension cost for defined benefit pension plan, Net of Tax Amount Other Comprehensive Income Loss Amortization Of Prior Service Cost And Actuarial Losses Include Net Periodic Pension Cost For Defined Benefit Pension Plan Net Of Tax Other comprehensive income amortization of prior service cost and actuarial losses included in net periodic pension cost for defined benefit pension plan, net of tax. Common Stock Issuable Common Stock Issuable [Member] Common stock issuable. Thereafter Sales-Type and Direct Financing Leases, Lease Receivable, To Be Received, After Year Four Sales-Type and Direct Financing Leases, Lease Receivable, To Be Received, After Year Four Other comprehensive income Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Other Comprehensive Income (Loss) Hedging Relationship [Domain] Hedging Relationship [Domain] Fair Values Derivatives, Balance Sheet Location, by Derivative Contract Type [Table] Fair Values Derivatives, Balance Sheet Location, by Derivative Contract Type [Table] Schedule of future minimum lease payments under operating leases Lessee, Operating Lease, Liability, Maturity [Table Text Block] Loans by aging category Financing Receivable, Recorded Investment, Aging [Abstract] Financing Receivable, Recorded Investment, Aging [Abstract] 2019 Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year Doubtful / Loss Doubtful [Member] Deposits Business Combination, Recognized Identifiable Assets Acquired And Liabilities Assumed, Deposits Business Combination, Recognized Identifiable Assets Acquired And Liabilities Assumed, Deposits Other operating expense Other Operating Expense [Member] Other Operating Expense Basic (in shares) Weighted Average Number of Shares Outstanding, Basic Basis spread on variable rate (spread) Debt Instrument, Basis Spread on Variable Rate Schedule of effect of derivatives in fair value hedging relationships on the consolidated statement of income Schedule of Fair Value Hedging Instruments, Statements of Financial Performance and Financial Position, Location [Table Text Block] Accrued expenses and other liabilities Increase (Decrease) in Accrued Liabilities and Other Operating Liabilities Common stock issued to dividend reinvestment plan and employee benefit plans Common Stock Issued To Dividend Reinvestment Plan and Employee Benefit Plans Value This element represents amount of common stock issued to dividend reinvestment plan and employee benefit plans. Outside services - electronic banking Noninterest Expense, Outside Services Electronic Banking Noninterest Expense, Outside Services Electronic Banking Cash flow hedging Cash Flow Hedging [Member] Summary of held to maturity securities in an unrealized loss position Debt Securities, Held-to-maturity, Continuous Unrealized Loss Position [Abstract] Carrying Amount Reported Value Measurement [Member] Derivative assets, measurement input Derivative Asset, Measurement Input Less: Amounts subject to master netting agreements Derivative Liability, Not Offset, Policy Election Deduction Preferred stock dividend per preferred share (in dollars per share) Preferred Stock, Dividends Per Share, Declared Common equity tier 1 capital, Minimum Common Equity Tier One Capital Required For Capital Adequacy To Risk Weighted Assets Common Equity Tier One Capital Required For Capital Adequacy To Risk Weighted Assets. Net increase in operating lease liability Right-of-Use Asset Obtained in Exchange for Operating Lease Liability Other Comprehensive Income (Loss), Defined Benefit Plan, Gain (Loss), Reclassification Adjustment from AOCI, before Tax Other Comprehensive Income (Loss), Defined Benefit Plan, Gain (Loss), Reclassification Adjustment from AOCI, before Tax Long-term debt Long-term Debt, Fair Value Schedule of Fair Value, Off-balance Sheet Risks [Table] Schedule of Fair Value, Off-balance Sheet Risks [Table] Pull through rate Measurement Input, Pull Through Rate [Member] Measurement Input, Pull Through Rate [Member] Income tax expense Net income, Tax (Expense) Benefit Income tax (expense) benefit Income Tax Expense (Benefit) Cash and cash equivalents, including restricted cash, at beginning of period Cash and cash equivalents, including restricted cash, at end of period Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents Debt Securities, Available-for-sale [Table] Debt Securities, Available-for-sale [Table] Title of Individual [Domain] Title of Individual [Domain] Local Phone Number Local Phone Number Cash consideration Cash consideration transferred Payments to Acquire Businesses, Gross Derivative Instruments and Hedging Activities Disclosure [Abstract] Derivative Instruments and Hedging Activities Disclosure [Abstract] Additions due to acquisitions Certain Loans Acquired in Transfer Accounted for as Debt Securities, Accretable Yield, Additions Cumulative Effect, Period of Adoption [Domain] Cumulative Effect, Period of Adoption [Domain] Schedule of estimated aggregate amortization expense for future periods for core deposit intangibles Finite-lived Intangible Assets Amortization Expense [Table Text Block] Accrued expenses and other liabilities Accrued Liabilities and Other Liabilities Actual revenue included since acquisition date Business Combination, Pro Forma Information, Revenue of Acquiree since Acquisition Date, Actual Compensation expense related to acceleration of vesting Share-based Payment Arrangement, Accelerated Cost Derivative [Line Items] Derivative [Line Items] Reconciliation of Liabilities at Level 3 Measurement Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] Regulatory Capital Requirements Under Banking Regulations [Abstract] Regulatory Capital Requirements Under Banking Regulations Long-term debt, gross Long-term Debt, Gross Available-for-Sale, Amortized Cost, More than 10 years Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, Rolling after 10 Years, Amortized Cost Amortization of prior service cost and actuarial losses included in net periodic pension cost for defined benefit pension plan, Tax (Expense) Benefit Other Comprehensive Income Loss Amortization Of Prior Service Cost And Actuarial Losses Included In Net Periodic Pension Cost For Defined Benefit Pension Plan Tax Expense Benefit1 Represents amount of other comprehensive income (loss) amortization of prior service cost and actuarial losses included in net periodic pension cost for defined benefit pension plan, tax expense benefit. Other assets and accrued interest receivable Increase (Decrease) in Other Operating Assets Exercise of stock options Stock Issued During Period, Value, Stock Options Exercised Reclassification of losses on derivative instruments realized in net income, Tax (Expense) Benefit Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), Reclassification, Tax Award Type [Axis] Award Type [Axis] Weighted- Average Grant- Date Fair Value Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract] Net unrealized gains, Tax (Expense) Benefit Other Comprehensive Income Loss Unrealized Holding Gain Loss On Securities Net Of Reclassification and Valuation Allowance Arising During Period Tax Effect Other comprehensive income loss unrealized holding gain loss on securities net of reclassification and valuation allowance arising during period tax effect. Class of Financing Receivable [Axis] Class of Financing Receivable [Axis] ACL Loans Financing Receivable, Allowance for Credit Losses, Policy for Uncollectible Amounts [Policy Text Block] Other assets Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Other Noncurrent Assets Financial instruments whose contract amounts represent credit risk: Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items] Retained Earnings (Accumulated Deficit) Retained earnings Retained Earnings [Member] Preferred stock outstanding (in shares) Preferred Stock, Shares Outstanding Measurement Basis [Axis] Measurement Basis [Axis] Other noninterest income Other Noninterest Income [Member] Information of other noninterest income [Member] Recorded Investment, With no related allowance recorded Impaired Financing Receivable, with No Related Allowance, Recorded Investment Allowance for credit losses - loans, Charge-Offs Financing Receivable, Allowance for Credit Loss, Writeoff Total allowance for credit losses, PCI Financing Receivable Allowance For Credit Loss And Off-Balance Sheet Credit Loss Liability, PCI Financing Receivable Allowance For Credit Loss And Off-Balance Sheet Credit Loss Liability, PCI Accounting Policies Significant Accounting Policies [Text Block] Net cash (used in) provided by investing activities Net Cash Provided by (Used in) Investing Activities Weighted-Average Remaining Contractual Term (Years), Outstanding Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Remaining Contractual Term Total Sales-type and Direct Financing Leases, Lease Receivable, Payments to be Received Award Type [Domain] Award Type [Domain] Deposits Deposit Balance Sheet Account [Member] Deposit Balance Sheet Account [Member] Estimate of contractual cash flows not expected to be collected Business Combination, Acquired Receivables, Estimated Uncollectible Schedule of balance and activity in the ACL by portfolio segment Financing Receivable, Allowance for Credit Loss [Table Text Block] Accretion Certain Loans Acquired in Transfer Accounted for as Debt Securities, Accretable Yield, Accretion Corporate bonds Corporate Debt Securities [Member] Commitments to extend credit Commitments to Extend Credit [Member] Loans Past Due, 60 - 89 Days Financial Asset, 60 to 89 Days Past Due [Member] Exercisable (in dollars per share) Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Weighted Average Exercise Price Fair value hedge Fair Value Hedge Assets Earnings Per Share Earnings Per Share [Text Block] Interest expense: Interest Expense [Abstract] Valuation technique Fair Value Measurements, Valuation Processes, Description Fair Value Adjustments Fair Value Adjustments Acquisition [Member] Fair Value Adjustments Acquisition [Member] FMBT First Madison Bank And Trust [Member] First Madison Bank And Trust [Member] Recently Adopted Standards and Accounting Standards Updates Not Yet Adopted New Accounting Pronouncements, Policy [Policy Text Block] Discount rate Measurement Input, Discount Rate [Member] Mortgage loans held for sale Fair value Mortgages Held-for-sale, Fair Value Disclosure Credit Loss Status [Axis] Credit Loss Status [Axis] Statement of Financial Position [Abstract] Statement of Financial Position [Abstract] Unpaid Principal Balance Impaired Financing Receivable, Unpaid Principal Balance [Abstract] Derivative liabilities Business Combination, Recognized Identifiable Assets Acquired And Liabilities Assumed, Noncurrent Liabilities, Derivatives Business Combination, Recognized Identifiable Assets Acquired And Liabilities Assumed, Noncurrent Liabilities, Derivatives