Goodwill and Intangible Assets Disclosure [Abstract] Goodwill and Other Intangible Assets Goodwill and Intangible Assets Disclosure [Text Block] Debt Disclosure [Abstract] Schedule of Extinguishment of Debt [Table] Schedule of Extinguishment of Debt [Table] Extinguishment of Debt [Axis] Extinguishment of Debt [Axis] Extinguishment of Debt, Type [Domain] Extinguishment of Debt, Type [Domain] FHLB Advances Federal Home Loan Bank Advances [Member] Extinguishment of Debt [Line Items] Extinguishment of Debt [Line Items] Extinguishment of long term debt Extinguishment of Debt, Amount Loss (gain) on early extinguishment of debt Gain (Loss) on Extinguishment of Debt Property, Plant and Equipment [Abstract] Rent expense applicable to operating leases Operating Leases, Rent Expense Rental income from owned properties and subleases Rental Income, Nonoperating Future minimum lease payments for operating leases Operating Leases, Future Minimum Payments Due, Fiscal Year Maturity [Abstract] 2018 Operating Leases, Future Minimum Payments Due, Next Twelve Months 2019 Operating Leases, Future Minimum Payments, Due in Two Years 2020 Operating Leases, Future Minimum Payments, Due in Three Years 2021 Operating Leases, Future Minimum Payments, Due in Four Years 2022 Operating Leases, Future Minimum Payments, Due in Five Years Thereafter Operating Leases, Future Minimum Payments, Due Thereafter Commitments and Contingencies Disclosure [Abstract] Letters of credit Letters of Credit Outstanding, Amount Carrying amount of the liability for letters of credit Guaranty Liabilities Investments in affordable housing and historic building rehabilitation projects: Investments in Affordable Housing Projects [Abstract] Carrying amount Investments In Affordable Housing Projects Investments in affordable housing and historic building rehabilitation projects Amount of future funding commitments included in carrying amount Qualified Affordable Housing Project Investments, Commitment Lending exposure Outstanding Loan Commitments To Affordable Housing Investments Outstanding loan commitments to affordable housing investments Tax credits subject to recapture Tax Credits Subject To Recapture Related To Affordable Housing Projects Tax Credits Subject To Recapture Related To Affordable Housing Projects Private equity investments Securities Owned Not Readily Marketable Future funding commitments to private equity investments Future Funding Commitments To Consolidated Private Equity Funds Future funding commitments to consolidated private equity funds Income Tax Disclosure [Abstract] Deferred tax assets: Deferred Tax Assets, Net [Abstract] ALLL Deferred Tax Assets, Tax Deferred Expense, Reserves and Accruals, Provision for Loan Losses Postretirement plans Deferred Tax Assets, Tax Deferred Expense, Compensation and Benefits, Postretirement Benefits Net unrealized loss on AFS securities Deferred Tax Assets, Unrealized Losses on Available-for-Sale Securities, Gross Equity-based compensation Deferred Tax Assets, Tax Deferred Expense, Compensation and Benefits, Share-based Compensation Cost Reserves and expense accruals Deferred Tax Assets, Tax Deferred Expense, Reserves and Accruals, Other Partnerships Deferred Tax Assets, Equity Method Investments Other Deferred Tax Assets, Tax Deferred Expense, Other Total deferred tax assets Deferred Tax Assets, Gross Deferred tax liabilities: Deferred Tax Liabilities, Gross [Abstract] Prepaid pension plan expense Deferred Tax Liabilities, Prepaid Expenses MSRs Deferred Tax Liabilities, Mortgage Servicing Rights Lease financing Deferred Tax Liabilities, Leasing Arrangements Loan fees and expenses Deferred Tax Liabilities, Deferred Expense, Other Capitalized Costs Identifiable intangible assets Deferred Tax Liabilities, Intangible Assets Other Deferred Tax Liabilities, Other Total deferred tax liabilities Deferred Tax Liabilities, Gross Net deferred tax asset (liability) Deferred Tax Liabilities, Net Net deferred tax asset (liability) Deferred Tax Assets, Net Statement of Comprehensive Income [Abstract] Net Income Net Income (Loss), Including Portion Attributable to Noncontrolling Interest OCI, Net of Tax: Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent [Abstract] Change in unrecognized net pension and postretirement costs Other Comprehensive (Income) Loss, Defined Benefit Plan, after Reclassification Adjustment, after Tax Change in unrealized net gains (losses) on cash flow hedges Other Comprehensive Income (Loss), Derivatives Qualifying as Hedges, Net of Tax Change in unrealized net gains (losses) on AFS securities Other Comprehensive Income (Loss), Unrealized Holding Gain (Loss) on Securities Arising During Period, Net of Tax Change in FDIC's share of unrealized gains/losses on AFS securities Net Change In Amounts Attributable To F D I C Under Loss Share Net Of Tax Represents the impact of changes in the fair value of securities available for sale that are subject to FDIC loss sharing agreements. This amount represents the FDIC's portion of the unrealized gains should these securities be sold, net of tax. Other, net Other Comprehensive Income, Other, Net of Tax Total OCI Other Comprehensive Income (Loss), Net of Tax Total comprehensive income Comprehensive Income (Loss), Net of Tax, Including Portion Attributable to Noncontrolling Interest Income Tax Effect of Items Included in OCI: Other Comprehensive Income (Loss), Tax, Portion Attributable to Parent, Parenthetical Disclosures [Abstract] Change in unrecognized net pension and postretirement costs Other Comprehensive (Income) Loss, Defined Benefit Plan, after Reclassification Adjustment, Tax Change in unrealized net gains (losses) on cash flow hedges Other Comprehensive Income (Loss), Derivatives Qualifying as Hedges, Tax Change in unrealized net gains (losses) on AFS securities Other Comprehensive Income (Loss), Unrealized Holding Gain (Loss) on Securities Arising During Period, Tax Change in FDIC 's share of unrealized gains/losses on AFS securities Net Change In Amounts Attributable To F D I C Under Loss Share Tax Portion Represents the impact of changes in the fair value of securities available for sale that are subject to FDIC loss sharing agreements. This amount represents the FDIC's portion of the unrealized gains should these securities be sold, tax portion. Other, net Other Comprehensive Income, Other, Net, Tax Tax effects of the increase (decrease) to accumulated comprehensive income during the period related to other, net Deposits [Abstract] Deposits Deposit Liabilities Disclosures [Text Block] Adjustment to income tax provision Tax Adjustments, Settlements, and Unusual Provisions Retirement Benefits [Abstract] Net Periodic Pension Cost: Defined Benefit Plan, Net Periodic Benefit Cost (Credit) [Abstract] Service cost Defined Benefit Plan, Service Cost Interest cost Defined Benefit Plan, Interest Cost Estimated return on plan assets Defined Benefit Plan, Expected Return (Loss) on Plan Assets Net amortization and other Defined Benefit Plan, Amortization of Gain (Loss) Net periodic benefit cost Defined Benefit Plan, Net Periodic Benefit Cost (Credit) Pre-Tax Amounts Recognized in OCI: Defined Benefit Plan, Amounts Recognized in Other Comprehensive Income (Loss) [Abstract] Prior service credit (cost) Other Comprehensive (Income) Loss, Defined Benefit Plan, Prior Service Cost (Credit), before Tax Net actuarial loss (gain) Other Comprehensive Income (Loss), Defined Benefit Plan, Gain (Loss) Arising During Period, before Tax Net amortization Other Comprehensive Income (Loss), Defined Benefit Plan, Gain (Loss), Reclassification Adjustment from AOCI, before Tax Net amount recognized in OCI Other Comprehensive Income (Loss), Defined Benefit Plan, Gain (Loss), after Reclassification Adjustment, before Tax Total net periodic pension costs (income) recognized in total comprehensive income, pre-tax Defined Benefit Plan, Amount Recognized in Net Periodic Benefit Cost (Credit) and Other Comprehensive (Income) Loss, before Tax Equity [Abstract] Schedule of Stock by Class [Table] Schedule of Stock by Class [Table] Class of Stock [Axis] Class of Stock [Axis] Class of Stock [Domain] Class of Stock [Domain] Series D Series D Preferred Stock [Member] Series E Series E Preferred Stock [Member] Series F Series F Preferred Stock [Member] Series G Series G Preferred Stock [Member] Series H Series H Preferred Stock [Member] Class of Stock [Line Items] Class of Stock [Line Items] Liquidation Amount Preferred Stock, Liquidation Preference, Value Carrying Amount Preferred Stock, Including Additional Paid in Capital, Net of Discount Dividend Rate Preferred Stock, Dividend Rate, Percentage Condensed Financial Information of Parent Company Only Disclosure [Abstract] Condensed Income Statement [Table] Condensed Income Statement [Table] Consolidated Entities [Axis] Consolidated Entities [Axis] Consolidated Entities [Domain] Consolidated Entities [Domain] Parent Company Parent Company [Member] Legal Entity [Axis] Legal Entity [Axis] Entity [Domain] Entity [Domain] Banking Banking Subsidiaries [Member] Banking Subsidiaries [Member] Nonbank Nonbank Subsidiaries [Member] Nonbank Subsidiaries [Member] Condensed Income Statements, Captions [Line Items] Condensed Income Statements, Captions [Line Items] Income: Revenues [Abstract] Dividends from subsidiaries Dividend Income, Operating Interest and other income from subsidiaries Other Interest and Dividend Income Other income Noninterest Income, Other Operating Income Total income Revenues Expenses: Operating Expenses [Abstract] Interest expense Interest Expense Other expenses Noninterest Expense Total expenses Operating Expenses Income before income taxes and equity in undistributed earnings of subsidiaries Income (Loss) from Continuing Operations before Equity Method Investments, Income Taxes, Noncontrolling Interest Income tax benefit Income Tax Expense (Benefit) Income before equity in undistributed earnings of subsidiaries Income Loss From Continuing Operations Before Income Loss From Equity Method Investments Income before equity in undistributed earnings of subsidiaries Equity in undistributed earnings of subsidiaries in excess of dividends from subsidiaries Income (Loss) from Equity Method Investments Net income Transfers and Servicing [Abstract] Schedule of Servicing Assets at Fair Value [Table] Schedule of Servicing Assets at Fair Value [Table] Financial Instrument [Axis] Financial Instrument [Axis] Financial Instruments [Domain] Financial Instruments [Domain] Residential MSRs Residential Mortgage [Member] Servicing Assets at Fair Value [Line Items] Servicing Assets at Fair Value [Line Items] Servicing Asset at Fair Value, Amount [Roll Forward] Servicing Asset at Fair Value, Amount [Roll Forward] Carrying value, beginning of year Servicing Asset at Fair Value, Amount Additions Servicing Asset at Fair Value, Additions Change in fair value due to changes in valuation inputs or assumptions: Servicing Asset at Fair Value, Changes in Fair Value Resulting from Changes in Valuation Inputs or Changes in Assumptions [Abstract] Prepayment speeds Prepayment Speed Assumption The net Increase or Decrease in fair value as a result of changes in the prepayment speed assumption used in the model to calculate the fair value of servicing assets. Weighted average OAS Oas Net Increase or Decrease in fair value as a result of changes in the OAS assumption used in the model to calculate the fair value of servicing assets. Servicing costs Servicing Costs The net increase or decrease in fair value as a result of changes in the servicing costs assumption used in the model to calculate the fair value of servicing assets. Realization of expected net servicing cash flows, passage of time and other Servicing Asset at Fair Value, Other Changes in Fair Value Carrying value, end of year Gains (losses) on derivative financial instruments used to mitigate the income statement effect of changes in fair value Gain (Loss) on Interest Rate Derivative Instruments Not Designated as Hedging Instruments Segment Reporting [Abstract] Number of reportable segments Number of Reportable Segments Derivative Instruments and Hedging Activities Disclosure [Abstract] Schedule of Derivative Financial Instruments and Related Hedged Items Schedule of Derivative Instruments [Table Text Block] The Effect of Derivative Instruments on the Consolidated Statements of Income Derivative Instruments, Gain (Loss) [Table Text Block] Deferred Gains and Losses From Cash Flow and Fair Value Hedges Deferred Gains And Losses From Hedges [Table Text Block] Tabular presentation of deferred gains and losses from hedges Schedule of Derivative Instruments Summary of Collateral Positions with Counterparties Schedule Of Derivative Instruments Summary Of Collateral Positions With Counterparties [Table Text Block] Schedule Of Derivative Instruments Summary Of Collateral Positions With Counterparties Statement of Cash Flows [Abstract] Cash Flows From Operating Activities: Net Cash Provided by (Used in) Operating Activities [Abstract] Adjustments to reconcile net income to net cash from operating activities: Adjustments to Reconcile Net Income (Loss) to Cash Provided by (Used in) Operating Activities [Abstract] Provision for credit losses Provision for Loan, Lease, and Other Losses Depreciation Depreciation, Nonproduction Loss (gain) on early extinguishment of debt Amortization of intangibles Amortization of Intangible Assets Equity-based compensation expense Share-based Compensation (Gain) loss on securities, net Gain (Loss) on Sale of Investments Net change in operating assets and liabilities: Increase (Decrease) in Operating Capital [Abstract] LHFS Increase (Decrease) in Loans Held-for-sale Trading securities Increase (Decrease) in Trading Securities Other assets, accounts payable and other liabilities Increase (Decrease) in Other Operating Assets and Liabilities, Net Cash paid to terminate FDIC loss share agreements Cash paid to terminate FDIC loss share agreements Represents cash paid to the FDIC to terminate FDIC loss share agreements. Other, net Other Operating Activities, Cash Flow Statement Net cash from operating activities Net Cash Provided by (Used in) Operating Activities Cash Flows From Investing Activities: Net Cash Provided by (Used in) Investing Activities [Abstract] Proceeds from sales of AFS securities Proceeds from Sale of Available-for-sale Securities Proceeds from maturities, calls and paydowns of AFS securities Proceeds from Maturities, Prepayments and Calls of Available-for-sale Securities Purchases of AFS securities Payments to Acquire Available-for-sale Securities Proceeds from maturities, calls and paydowns of HTM securities Proceeds from Maturities, Prepayments and Calls of Held-to-maturity Securities Purchases of HTM securities Payments to Acquire Held-to-maturity Securities Originations and purchases of loans and leases, net of principal collected Payments for (Proceeds from) Loans and Leases Net cash received (paid) for acquisitions and divestitures Payments to Acquire Businesses, Net of Cash Acquired Other, net Payments for (Proceeds from) Other Investing Activities Net cash from investing activities Net Cash Provided by (Used in) Investing Activities Cash Flows From Financing Activities: Net Cash Provided by (Used in) Financing Activities [Abstract] Net change in deposits Increase (Decrease) in Deposits Net change in short-term borrowings Proceeds from (Repayments of) Other Debt Proceeds from issuance of long-term debt Proceeds from Issuance of Long-term Debt Repayment of long-term debt Repayments of Long-term Debt Repurchase of common stock Payments for Repurchase of Common Stock Net cash from common stock transactions in connection with equity awards Proceeds from Issuance of Shares under Incentive and Share-based Compensation Plans, Including Stock Options Net proceeds from preferred stock issued Proceeds from Issuance of Preferred Stock and Preference Stock Cash dividends paid on common stock Payments of Ordinary Dividends, Common Stock Cash dividends paid on preferred stock Payments of Ordinary Dividends, Preferred Stock and Preference Stock Other, net Proceeds from (Payments for) Other Financing Activities Net cash from financing activities Net Cash Provided by (Used in) Financing Activities Net Change in Cash and Cash Equivalents Cash and Cash Equivalents, Period Increase (Decrease) Cash and Cash Equivalents at Beginning of Period Cash and Cash Equivalents, at Carrying Value Cash and Cash Equivalents at End of Period Supplemental Disclosure of Cash Flow Information: Additional Cash Flow Elements and Supplemental Cash Flow Information [Abstract] Cash paid during the period for: Supplemental Cash Flow Information [Abstract] Interest Interest Paid, Net Income taxes Income Taxes Paid, Net Noncash investing and financing activities: Cash Flow, Noncash Investing and Financing Activities Disclosure [Abstract] Transfers of loans to foreclosed assets Real Estate Owned, Transfer from Real Estate Owned Transfers of loans HFI to LHFS Transfer of Portfolio Loans and Leases to Held-for-sale Stock issued in acquisitions Stock Issued Purchase of additional interest in AmRisc, LP Purchase of Additional Ownership in Subsidiary, Noncash Noncash portion of the purchase price of additional ownership of Subsidiary Transfer of HTM securities to AFS Transfer from Investments Accounting Policies [Abstract] Reclassifications Schedule of Error Corrections and Prior Period Adjustments [Table Text Block] Schedule of Loans and Leases Past Due Policies Schedule of Loans and Leases Past Due Policies [Table Text Block] Schedule of Loans and Leases Past Due Policies [Table Text Block] Receivables [Abstract] Unearned income, discounts and net deferred loan fees and costs, excluding PCI Loans and Leases Receivable, Deferred Income Residential mortgage loans in process of foreclosure Mortgage Loans in Process of Foreclosure, Amount Investments, Debt and Equity Securities [Abstract] Summary of Amortized Cost, Gross Unrealized Gains and Approximate Fair Values of AFS Securities Available-for-sale Securities [Table Text Block] Summary of Summary of Amortized Cost, Gross Unrealized Gains and Approximate Fair Values of HTM Securities Held-to-maturity Securities [Table Text Block] Schedule of Amortized Cost and Estimated Fair Value by Contractual Maturity Investments Classified by Contractual Maturity Date [Table Text Block] Schedule of Fair Values and Gross Unrealized Losses of Investments by Investment Category and Length of Time Schedule of Unrealized Loss on Investments [Table Text Block] Reconciliation of Revenue from Segments to Consolidated [Table] Reconciliation of Revenue from Segments to Consolidated [Table] Consolidation Items [Axis] Consolidation Items [Axis] Consolidation Items [Domain] Consolidation Items [Domain] Operating Segments Operating Segments [Member] Intersegment Eliminations Intersegment Eliminations [Member] Segments [Axis] Segments [Axis] Segments [Domain] Segments [Domain] CB-Retail Community Banking Retail and Consumer Finance [Member] Community Banking Retail and Consumer Finance [Member] FS&CF Financial Services and Commercial Finance [Member] Financial Services and Commercial Finance [Member] IH&PF Insurance Holdings and Premium Finance [Member] Insurance Holdings and Premium Finance [Member] OT&C (1) Other, Treasury & Corporate [Member] Other, Treasury & Corporate [Member] Segment Reporting, Revenue Reconciling Items [Line Items] Segment Reporting, Revenue Reconciling Item [Line Items] Net interest income (expense) Interest Income (Expense), Net Allocated provision for credit losses Segment net interest income after provision Interest Income (Expense), after Provision for Loan Loss Noninterest income Noninterest Income Noninterest expense Provision (benefit) for income taxes Identifiable assets (period end) Assets Goodwill Activity by Operating Segment Schedule of Goodwill [Table Text Block] Identifiable Intangible Assets Subject to Amortization Schedule of Finite-Lived Intangible Assets [Table Text Block] Future Amortization Expense of Identifiable Intangible Assets Schedule of Finite-Lived Intangible Assets, Future Amortization Expense [Table Text Block] Trading Securities [Table] Trading Securities [Table] Investment [Axis] Investment [Axis] Investment [Domain] Investment [Domain] U.S. Treasury US Treasury Securities [Member] States and political subdivisions US States and Political Subdivisions Debt Securities [Member] Other Other Debt Obligations [Member] Schedule of Trading Securities and Other Trading Assets [Line Items] Schedule of Trading Securities and Other Trading Assets [Line Items] AFS securities, Fair Value Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value [Abstract] Less than 12 months Available-for-sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value 12 months or more Available-for-sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value Total Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value AFS securities, Unrealized Losses Available-for-sale Securities, Continuous Unrealized Loss Position, Aggregate Loss [Abstract] Less than 12 months Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss 12 months or more Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss Total Available-for-sale Securities, Continuous Unrealized Loss Position, Accumulated Loss HTM securities, Fair Value Held-to-maturity Securities, Continuous Unrealized Loss Position, Fair Value [Abstract] Less than 12 months Held-to-maturity Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value 12 months or more Held-to-maturity Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value Total Held-to-maturity Securities, Continuous Unrealized Loss Position, Fair Value HTM securities, Unrealized Losses Held-to-maturity Securities, Continuous Unrealized Loss Position, Aggregate Loss [Abstract] Less than 12 months Held-to-maturity Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss 12 months or more Held-to-maturity Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss Total Held-to-maturity Securities, Continuous Unrealized Loss Position, Accumulated Loss Federal income taxes at statutory rate of 35% Effective Income Tax Rate Reconciliation at Federal Statutory Income Tax Rate, Amount Increase (decrease) in provision for income taxes as a result of: Effective Income Tax Rate Reconciliation, Amount [Abstract] State income taxes, net of federal tax benefit Effective Income Tax Rate Reconciliation, State and Local Income Taxes, Amount Affordable housing projects proportional amortization Amortization Method Qualified Affordable Housing Project Investments, Amortization Affordable housing projects tax credits and other tax benefits Affordable Housing Tax Credits and Other Tax Benefits, Amount Tax exempt income Effective Income Tax Rate Reconciliation, Tax Exempt Income, Amount Federal tax reform impact Tax Cuts and Jobs Act of 2017, Income Tax Expense (Benefit) Amount of income tax expense (benefit) from effect of Tax Cuts and Jobs Act of 2017. Excess tax benefits for equity-based compensation Employee Service Share-based Compensation, Tax Benefit from Exercise of Stock Options Adjustments for uncertain tax positions Effective Income Tax Rate Reconciliation, Tax Contingency, Domestic, Amount Other, net Effective Income Tax Rate Reconciliation, Other Adjustments, Amount Provision for income taxes Effective income tax rate Effective Income Tax Rate Reconciliation, Percent Current expense: Current Income Tax Expense (Benefit), Continuing Operations [Abstract] Federal Current Federal Tax Expense (Benefit) State Current State and Local Tax Expense (Benefit) Total current expense Current Income Tax Expense (Benefit) Deferred expense: Deferred Income Tax Expense (Benefit), Continuing Operations [Abstract] Federal Deferred Federal Income Tax Expense (Benefit) State Deferred State and Local Income Tax Expense (Benefit) Total deferred expense Deferred Income Tax Expense (Benefit) Summary of Deposits Deposit Liabilities, Type [Table Text Block] Long-Term Debt Long-term Debt [Text Block] Fair Value Disclosures [Abstract] Schedule of Assets and Liabilities Measured at Fair Value Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis [Table Text Block] Roll Forward of Level 3 Assets and Liabilities Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Table Text Block] Fair Value and UPB of LHFS Fair Value, Option, Quantitative Disclosures [Table Text Block] Financial Assets Measured at Fair Value on Nonrecurring Basis Fair Value Measurements, Nonrecurring [Table Text Block] Carrying Amounts and Fair Values of Financial Assets and Liabilities Not Recorded at Fair Value Fair Value, by Balance Sheet Grouping [Table Text Block] Notional or Contractual Amounts and Fair Values of Off-Balance Sheet Financial Instruments Schedule of Fair Value, Off-balance Sheet Risks [Table Text Block] Income Taxes Income Tax Disclosure [Text Block] Summary of Residential Mortgage Banking Activities Residential Mortgage Banking Activities [Table Text Block] Presents a summary of information related to residential mortgage banking activities including a reconciliation of mortgage loans managed to mortgage loans held for investment on the balance sheet; along with past due, nonaccrual and charge-off data related to these loans. Also includes details about the servicing portfolio, recourse and repurchase exposure and loan sales occurring during the period Analysis of Activity in Residential MSRs Schedule of Servicing Assets at Fair Value [Table Text Block] Residential MSRs Sensitivity Schedule of Sensitivity Analysis of Fair Value, Transferor's Interests in Transferred Financial Assets [Table Text Block] Summary of Commercial Mortgage Banking Activities Summary of Commercial Mortgage Banking Activities [Table Text Block] Summary of Commercial Mortgage Banking Activities Schedule of Credit Derivatives [Table] Schedule of Credit Derivatives [Table] Credit Derivatives Contract Type [Axis] Credit Derivatives Contract Type [Axis] Credit Derivatives Contract Type [Domain] Credit Derivatives Contract Type [Domain] Dealer Counterparties Dealer Counterparties [Member] Dealer Counterparties [Member] Central Clearing Parties Central Clearing Parties [Member] Central Clearing Parties [Member] Credit Derivatives [Line Items] Credit Derivatives [Line Items] Cash collateral received from dealer counterparties Derivative, Collateral, Obligation to Return Cash Derivatives in a net gain position secured by collateral received Derivative Asset, Fair Value, Amount Offset Against Collateral Unsecured positions in a net gain with dealer counterparties after collateral postings Derivative Asset, Fair Value, Amount Not Offset Against Collateral Cash collateral posted Derivative, Collateral, Right to Reclaim Cash Derivatives in a net loss position secured by collateral posted Derivative Liability, Fair Value, Amount Offset Against Collateral Additional collateral that would have been posted had BB&T's credit ratings dropped below investment grade Increase Decrease Posted Collateral Increase in the aggregate fair value of assets that are required to be posted as collateral for derivative instruments in the event of a credit ratings downgrade below investment grade. Securities pledged to central clearing parties Security Owned and Pledged as Collateral, Fair Value Schedule of Selected Financial Information Regarding Reportable Business Segments Schedule of Segment Reporting Information, by Segment [Table Text Block] Regulatory Capital Requirements [Abstract] Summary Information Regarding Regulatory Capital Schedule of Compliance with Regulatory Capital Requirements under Banking Regulations [Table Text Block] Derivative [Table] Derivative [Table] Hedging Relationship [Axis] Hedging Relationship [Axis] Hedging Relationship [Domain] Hedging Relationship [Domain] Cash flow hedges Cash Flow Hedging [Member] Fair value hedges Fair Value Hedging [Member] Derivative [Line Items] Derivative [Line Items] Cash flow hedges: Effect of Cash Flow Hedges on Results of Operations [Abstract] Net unrecognized after-tax loss on active hedges recorded in AOCI Net unrecognized after tax loss on active hedges recorded in AOCI Net unrecognized after tax loss on active hedges recorded in AOCI. Net unrecognized after-tax gain on terminated hedges recorded in AOCI (to be recognized in earnings through 2022) Net unrecognized after tax gain on terminated hedges recorded in AOCI to be recognized thru 2022 Net unrecognized after tax gain on terminated hedges recorded in AOCI to be recognized in future periods Estimated portion of net after-tax loss on active and terminated hedges to be reclassified from AOCI into earnings during the next 12 months Cash Flow Hedge Gain (Loss) to be Reclassified within Twelve Months Maximum time period over which BB&T has hedged a portion of the variability in future cash flows for forecasted transactions excluding those transactions relating to the payment of variable interest on existing instruments Maximum length of time entity has hedged portion of variable cash flows for forecasted transactions (in years) Maximum length of time entity has hedged portion of variable cash flows for forecasted transactions (in years) Fair value hedges: Effect of Fair Value Hedges on Results of Operations [Abstract] Unrecognized pre-tax net gain on terminated hedges (to be recognized as interest primarily through 2019) Unrecognized pre-tax gain on terminated hedges to be recognized as interest primarily through 2019 Unrecognized pre-tax gain on terminated hedges to be recognized as interest in future periods Portion of pre-tax net gain on terminated hedges to be recognized as a change in interest during the next 12 months Portion of pre-tax gain on terminated hedges to be recognized as a change in interest expense during the next 12 months Portion of pre-tax gain on terminated hedges to be recognized as a change in interest expense during the next 12 months Summary of Non-Cumulative Perpetual Preferred Stock Schedule of Stock by Class [Table Text Block] Summary of Selected Information Pertaining to Equity-based Compensation Plans Share-based Compensation Arrangements by Share-based Payment Award, Options, Vested and Expected to Vest, Outstanding [Table Text Block] Summary of Selected Data Related to Equity-based Compensation Costs Disclosure of Share-based Compensation Arrangements by Share-based Payment Award [Table Text Block] Rollforward of RSUs, PSUs amd Restricted Shares Schedule of Share-based Compensation, Restricted Stock and Restricted Stock Units Activity [Table Text Block] Earnings Per Share [Abstract] Net income available to common shareholders Net Income (Loss) Available to Common Stockholders, Basic Weighted average number of common shares (in shares) Weighted Average Number of Shares Outstanding, Basic Effect of dilutive outstanding equity-based awards (in shares) Incremental Common Shares Attributable to Dilutive Effect of Share-based Payment Arrangements Weighted average number of diluted common shares (in shares) Weighted Average Number of Shares Outstanding, Diluted Basic EPS (in usd per share) Earnings Per Share, Basic Diluted EPS (in usd per share) Earnings Per Share, Diluted Anti-dilutive awards (in shares) Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount Future debt maturities Long-term Debt, Fiscal Year Maturity [Abstract] 2018 Long-term Debt, Maturities, Repayments of Principal in Next Twelve Months 2019 Long-term Debt, Maturities, Repayments of Principal in Year Two 2020 Long-term Debt, Maturities, Repayments of Principal in Year Three 2021 Long-term Debt, Maturities, Repayments of Principal in Year Four 2022 Long-term Debt, Maturities, Repayments of Principal in Year Five Thereafter Long-term Debt, Maturities, Repayments of Principal after Year Five Loan Servicing Transfers and Servicing of Financial Assets [Text Block] Loans and Leases Receivable Disclosure [Table] Loans and Leases Receivable Disclosure [Table] Financing Receivable Portfolio Segment [Axis] Financing Receivable Portfolio Segment [Axis] Financing Receivable Portfolio Segment [Domain] Financing Receivable Portfolio Segment [Domain] Commercial Commercial Portfolio Segment [Member] Retail Consumer Portfolio Segment [Member] Revolving credit Credit Card Receivable [Member] Class of Financing Receivable, Type [Axis] Class of Financing Receivable, Type [Axis] Class of Financing Receivable, Type [Domain] Class of Financing Receivable, Type [Domain] Commercial and industrial Commercial and Industrial [Member] Commercial And Industrial [Member] CRE Commercial Real Estate [Member] Lease financing Finance Leases Portfolio Segment [Member] Residential mortgage Direct Direct Lending [Member] Direct Lending [Member] Indirect Indirect Lending [Member] Indirect Lending [Member] Range [Axis] Range [Axis] Range [Domain] Range [Domain] Minimum Minimum [Member] Maximum Maximum [Member] Loans and Leases Receivable Disclosure [Line Items] Loans and Leases Receivable Disclosure [Line Items] Threshold period for nonaccrual status classification of loans Threshold Period Past Due for Nonaccrual Status of Loans and Leases Receivable Threshold Period Past Due for Nonaccrual Status of Loans and Leases Receivable Threshold period past due for charge down of loans Threshold Period Past Due for Write-off of Financing Receivable Sustained performance period to return to accrual status Sustained Performance Period To Return To Accrual Status Sustained Performance Period To Return To Accrual Status Threshold period for past due classification of loans and leases receivable Threshold Period Past Due Classification for Loans and Leases Receivable Threshold Period Past Due Classification for Loans and Leases Receivable Collateral on impaired loans and foreclosed properties, valuation period Collateral, Valuation Period Collateral, Valuation Period Threshold amount for annual risk ratings review (or more) Financing Receivable, Threshold for Annual Risk Ratings Review Financing Receivable, Threshold for Annual Risk Ratings Review Threshold amount to be subjected to automated loan review system that produces a score for evaluating reserves (less than) Financing Receivable, Threshold for Automated Loan Review System Threshold to be subjected to automated loan review system that produces a score for evaluating reserves Threshold amount to establish a reserve on nonaccrual loans (or more) Financing Receivable, Threshold Amount for Review in Determining Reserves, Nonaccrual Status Financing Receivable, Threshold Amount for Review in Determining Reserves, Nonaccrual Status Threshold amount to establish a reserve on collateral dependent loans based upon the underlying collateral value, net of costs to sell Financing Receivable, Threshold Amount to Establish Reserve Based on Underlying Collateral Value, Net of Costs to Sell Financing Receivable, Threshold Amount to Establish Reserve Based on Underlying Collateral Value, Net of Costs to Sell Schedule of Long Term Debt, Interest Rates and Maturity Dates Schedule of Long-term Debt Instruments [Table Text Block] Schedule of Future Maturities of Long-Term Debt Schedule of Maturities of Long-term Debt [Table Text Block] Fixed Rate Residential Mortgage Fixed Rate Residential Mortgage [Member] Adjustable Rate Residential Mortgage Adjustable Rate Residential Mortgage [Member] Min Max Weighted Average Weighted Average [Member] Prepayment speed Assumption for Fair Value of Assets or Liabilities that relate to Transferor's Continuing Involvement, Prepayment Speed Effect on fair value of a 10% increase Sensitivity Analysis of Fair Value, Transferor's Interests in Transferred Financial Assets, Impact of 10 Percent Adverse Change in Prepayment Speed Effect on fair value of a 20% increase Sensitivity Analysis of Fair Value, Transferor's Interests in Transferred Financial Assets, Impact of 20 Percent Adverse Change in Prepayment Speed OAS Option adjusted spread Option adjusted spread assumption used in valuing MSRs Effect on fair value of a 10% increase Sensitivity Analysis Of Fair Value Of 10 Percent Increase In Weighted Average OAS Effect on fair value of a 10% increase in weighted average OAS Effect on fair value of a 20% increase Sensitivity Analysis Of Fair Value Of 20 Percent Increase In Weighted Average OAS Effect on fair value of a 20% increase in weighted average OAS Composition of loans serviced for others Percentage Of Mortgage Loans Serviced For Others Composition Of Mortgage Loans Serviced For Others Weighted average life (in years) Assumption for Fair Value of Assets or Liabilities that relate to Transferor's Continuing Involvement, Weighted Average Life Schedule of Long-term Debt Instruments [Table] Schedule of Long-term Debt Instruments [Table] BB&T Corporation: Branch Bank Subsidiaries [Member] Long-term Debt, Type [Axis] Long-term Debt, Type [Axis] Long-term Debt, Type [Domain] Long-term Debt, Type [Domain] Senior Notes Senior Notes [Member] Subordinated Notes Subordinated Debt [Member] Debt Instrument [Axis] Debt Instrument [Axis] Debt Instrument, Name [Domain] Debt Instrument, Name [Domain] Fixed rate Fixed Rate [Member] Fixed Rate [Member] Floating rate Floating Rate [Member] Floating Rate [Member] Other long-term debt Other Long-Term Debt [Member] Represents other forms of long-term debt not presented elsewhere in the long-term debt footnote table. Debt Instrument [Line Items] Debt Instrument [Line Items] Stated Rate Debt Instrument, Interest Rate, Stated Percentage Effective Rate Debt Instrument, Interest Rate, Effective Percentage Long-term debt Long-term Debt Other long-term debt Other Long-term Debt Weighted average maturity of FHLB advances Weighted average maturity of FHLB advances Weighted average maturity of FHLB advances Derivative Instruments, Gain (Loss) [Table] Derivative Instruments, Gain (Loss) [Table] Client-related and other risk management Client-Related and Other Risk Management [Member] Client-Related and Other Risk Management Mortgage banking Mortgages [Member] MSRs Servicing Contracts [Member] Hedging Designation [Axis] Hedging Designation [Axis] Hedging Designation [Domain] Hedging Designation [Domain] Not designated as hedges Not Designated as Hedging Instrument [Member] Derivative, by Nature [Axis] Derivative Instrument [Axis] Derivative Contract [Domain] Derivative Contract [Domain] Interest rate contracts Interest Rate Contract [Member] Foreign exchange contracts Foreign Exchange Contract [Member] Pay fixed swaps Pay Fixed Swaps [Member] Derivative contract to pay a fixed interest rate obligation or instrument and receive a floating interest rate obligation or instrument. Receive fixed swaps Receive Fixed Swaps [Member] Derivative contract to receive a fixed interest rate obligation or instrument and pay a floating interest rate obligation or instrument. Options Option Trades [Member] Option trades [Member] Other swaps Other Swaps [Member] Other swaps [Member] Interest rate lock commitments Interest Rate Lock Commitments [Member] When issued securities, forward rate agreements and forward commitments When Issued Securities And Forward Rate Agreements And Forward Commitments [Member] Forward rate agreements are contracts between two counterparties whereby one counterparty agrees to pay a floating rate of interest and the other commits to pay a floating rate of interest on a predetermined notional amount. Other Other Derivatives [Member] Forward commitments Forward Commitments [Member] Balance Sheet Location [Axis] Balance Sheet Location [Axis] Balance Sheet Location [Domain] Balance Sheet Location [Domain] 3 mo. LIBOR funding London Interbank Offered Rate (LIBOR) [Member] Long-term debt Long-term Debt [Member] Commercial loans Commercial Loan [Member] Municipal securities Municipal Bonds [Member] Derivative Instruments, Gain (Loss) [Line Items] Derivative Instruments, Gain (Loss) [Line Items] Hedge ineffectiveness Fair Value Hedge Ineffectiveness is Immaterial Assertion Notional Amount Derivative, Notional Amount Fair Value, Gain Derivative Asset, Fair Value, Gross Asset Fair Value, Loss Derivative Liability, Fair Value, Gross Liability Gross amounts not offset in the Consolidated Balance Sheets: Fair Value, Gain Derivative Asset [Abstract] Amounts subject to master netting arrangements not offset due to policy election Derivative Asset, Not Offset, Policy Election Deduction Cash collateral (received) posted Net amount Derivative Asset, Fair Value, Offset Against Collateral, Net of Not Subject to Master Netting Arrangement, Policy Election Gross amounts not offset in the Consolidated Balance Sheets: Fair Value, Loss Derivative Liability [Abstract] Amounts subject to master netting arrangements not offset due to policy election Derivative Liability, Not Offset, Policy Election Deduction Cash collateral (received) posted Net amount Derivative Liability, Fair Value, Offset Against Collateral, Net of Not Subject to Master Netting Arrangement, Policy Election Schedule of Defined Benefit Plans Disclosures [Table] Schedule of Defined Benefit Plans Disclosures [Table] Retirement Plan Tax Status [Axis] Retirement Plan Tax Status [Axis] Retirement Plan Tax Status [Domain] Retirement Plan Tax Status [Domain] Qualified Plan Qualified Plan [Member] Nonqualified Plans Nonqualified Plan [Member] Defined Benefit Plan Disclosure [Line Items] Defined Benefit Plan Disclosure [Line Items] Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] Fair value of plan assets, beginning of year Defined Benefit Plan, Fair Value of Plan Assets Actual return on plan assets Defined Benefit Plan, Plan Assets, Increase (Decrease) for Actual Return (Loss) Employer contributions Defined Benefit Plan, Plan Assets, Contributions by Employer Benefits paid Defined Benefit Plan, Plan Assets, Benefits Paid Acquisitions Defined Benefit Plan, Plan Assets, Business Combination Fair value of plan assets, end of year Funded status at end of year Defined Benefit Plan, Funded (Unfunded) Status of Plan Summary of Significant Accounting Policies Basis of Presentation and Significant Accounting Policies [Text Block] Schedule of Available-for-sale Securities [Table] Schedule of Available-for-sale Securities [Table] FNMA investments Federal National Mortgage Association Certificates and Obligations (FNMA) [Member] FHLMC investments Federal Home Loan Mortgage Corporation Certificates and Obligations (FHLMC) [Member] Non-agency MBS Mortgage-backed Securities, Issued by Private Enterprises [Member] Schedule of Available-for-sale Securities [Line Items] Schedule of Available-for-sale Securities [Line Items] Securities, amortized cost Securities Amortized Cost Debt and equity financial instruments including: (1) securities held-to-maturity, (2) trading securities, and (3) securities available-for-sale at amortized cost. Securities, fair value Marketable Securities Number of securities with other than temporary credit impairment Other than Temporary Credit Impairment, Number of Securities Other than Temporary Credit Impairment, Number of Securities Defined Benefit Plans and Other Postretirement Benefit Plans Disclosures [Table] Defined Benefit Plans and Other Postretirement Benefit Plans Disclosures [Table] Scenario [Axis] Scenario [Axis] Scenario, Unspecified [Domain] Scenario, Unspecified [Domain] Forecast Scenario, Forecast [Member] Subsequent Event Type [Axis] Subsequent Event Type [Axis] Subsequent Event Type [Domain] Subsequent Event Type [Domain] Subsequent Event Subsequent Event [Member] Defined Benefit Plan, Asset Categories [Axis] Defined Benefit Plan, Asset Categories [Axis] Plan Asset Categories [Domain] Plan Asset Categories [Domain] U.S. Equity Securities Equity Securities [Member] International Equity Securities International Equity Securities [Member] This category includes information about ownership interests or the right to acquire ownership interests in foreign corporations and other legal entities which ownership interest is represented by shares of common or preferred stock (which is neither mandatorily redeemable no redeemable at the option of the holder), convertible securities, stock rights, or stock warrants. Fixed Income Securities Fixed Income Securities [Member] Alternative Investments Alternative Investments [Member] This element represents all other investment not specifically defined in the taxonomy. Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] Defined benefit plan, number of highest consecutive years of earnings Defined Benefit Plan, Number of Highest Consecutive Years of Earnings Defined Benefit Plan, Number of Highest Consecutive Years of Earnings Defined benefit plan, final years of employment subject to earnings test Defined Benefit Plan, Employment Period Defined Benefit Plan, Employment Period Weighted average expected long-term rate of return on plan assets Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Expected Long-term Rate of Return on Plan Assets Discretionary contributions made to the qualified pension plan Payment for Pension Benefits Defined Benefit Plan, Plan Assets, Target Allocation, Percentage Defined Benefit Plan, Plan Assets, Target Allocation, Percentage Net asset values Defined contribution plan, employee contribution percentage, minimum Defined Contribution Plan Employee Contribution Percentage Of Cash Compensation, Minimum Defined Contribution Plan Employee Contribution Percentage Of Cash Compensation, Minimum Defined contribution plan, employee contribution percentage, maximum Defined Contribution Plan, Maximum Annual Contributions Per Employee, Percent Defined contribution plan, minimum age of employees covered Defined Contribution Plan, Age of Employees Covered Defined Contribution Plan, Age of Employees Covered Defined contribution plan, minimum years of service of employees covered Defined Contribution Plan, Number of Years of Service of Employees Covered Defined Contribution Plan, Number of Years of Service of Employees Covered Defined contribution plan, employer matching contribution, percentage of employee compensation, maximum Defined Contribution Plan, Employer Matching Contribution, Percent of Employees' Gross Pay Defined contribution plan, employer contribution expense Defined Contribution Plan, Cost AFS, Amortized Cost Available-for-sale Securities, Debt Maturities, Single Maturity Date, Amortized Cost Basis [Abstract] Due in one year or less Available-for-sale Securities, Debt Maturities, Next Twelve Months, Amortized Cost Basis Due after one year through five years Available-for-sale Securities, Debt Maturities, Year Two Through Five, Amortized Cost Basis Due after five years through ten years Available-for-sale Securities, Debt Maturities, Year Six Through Ten, Amortized Cost Basis Due after ten years Available-for-sale Securities, Debt Maturities, after Ten Years, Amortized Cost Basis Total debt securities Available-for-sale Debt Securities, Amortized Cost Basis AFS, Fair Value Available-for-sale Securities, Debt Maturities, Single Maturity Date [Abstract] Due in one year or less Available-for-sale Securities, Debt Maturities, Next Twelve Months, Fair Value Due after one year through five years Available-for-sale Securities, Debt Maturities, Year Two Through Five, Fair Value Due after five years through ten years Available-for-sale Securities, Debt Maturities, Year Six Through Ten, Fair Value Due after ten years Available-for-sale Securities, Debt Maturities, after Ten Years, Fair Value Total debt securities Available-for-sale Securities, Debt Securities HTM, Amortized Cost Held-to-maturity Securities, Debt Maturities, Single Maturity Date, Amortized Cost Basis [Abstract] Due in one year or less Held-to-maturity Securities, Debt Maturities, within One Year, Net Carrying Amount Due after one year through five years Held-to-maturity Securities, Debt Maturities, after One Through Five Years, Net Carrying Amount Due after five years through ten years Held-to-maturity Securities, Debt Maturities, after Five Through Ten Years, Net Carrying Amount Due after ten years Held-to-maturity Securities, Debt Maturities, after Ten Years, Net Carrying Amount Amortized Cost Held-to-maturity Securities HTM, Fair Value Held-to-maturity Securities, Debt Maturities, Single Maturity Date, Fair Value [Abstract] Due in one year or less Held-to-maturity Securities, Debt Maturities, Next Twelve Months, Fair Value Due after one year through five years Held-to-maturity Securities, Debt Maturities, Year Two Through Five, Fair Value Due after five years through ten years Held-to-maturity Securities, Debt Maturities, Year Six Through Ten, Fair Value Due after ten years Held-to-maturity Securities, Debt Maturities, after Ten Years, Fair Value Total debt securities Held-to-maturity Securities, Fair Value Derivative Financial Instruments Derivative Instruments and Hedging Activities Disclosure [Text Block] 2018 Defined Benefit Plan, Expected Future Benefit Payment, Next Twelve Months 2019 Defined Benefit Plan, Expected Future Benefit Payment, Year Two 2020 Defined Benefit Plan, Expected Future Benefit Payment, Year Three 2021 Defined Benefit Plan, Expected Future Benefit Payment, Year Four 2022 Defined Benefit Plan, Expected Future Benefit Payment, Year Five 2023-2027 Defined Benefit Plan, Expected Future Benefit Payment, Five Fiscal Years Thereafter Fair Value Measurements, Recurring and Nonrecurring [Table] Fair Value Measurements, Recurring and Nonrecurring [Table] Net Derivatives Derivative [Member] Private Equity Investments Private Equity Funds [Member] 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] Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] Balance at beginning of period Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value Included in earnings Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Earnings Included in unrealized net holding gains (losses) in OCI Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Other Comprehensive Income (Loss) Purchases Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Purchases Issuances Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Issuances Sales Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Sales Settlements Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Settlements Transfers into Level 3 Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Transfers Into Level 3 Transfers out of Level 3 Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Transfers out of Level 3 Adoption of fair value option for commercial MSRs Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Other Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Other Balance at end of period Change in unrealized gains (losses) included in earnings attributable to asset and liabilities still held at period end Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Change in Unrealized Gain (Loss) Premises and Equipment [Table] Property, Plant and Equipment [Table] Premises and Equipment, Type [Axis] Property, Plant and Equipment, Type [Axis] Premises and Equipment, Type [Domain] Property, Plant and Equipment, Type [Domain] Land and land improvements Land and Land Improvements [Member] Buildings and building improvements Building and Building Improvements [Member] Furniture and equipment Furniture and Fixtures [Member] Leasehold improvements Leasehold Improvements [Member] Construction in progress Construction in Progress [Member] Capitalized leases on premises and equipment Assets Held under Capital Leases [Member] Property, Plant and Equipment [Line Items] Property, Plant and Equipment [Line Items] Estimated Useful Life (Years) Property, Plant and Equipment, Useful Life Total Property, Plant and Equipment, Gross Accumulated depreciation and amortization Accumulated Depreciation, Depletion and Amortization, Property, Plant, and Equipment Net premises and equipment Property, Plant and Equipment, Net Schedule of Financing Receivable, Troubled Debt Restructurings [Table] Schedule of Financing Receivable, Troubled Debt Restructurings [Table] Receivable Type [Axis] Receivable Type [Axis] Receivable [Domain] Receivable [Domain] Newly Designated TDRs [Member] Newly Designated TDRs [Member] Loans that are modified as a TDR that were not previously designated as a TDR Re-Modification of Previously Designated TDRs [Member] Re-Modification of Previously Designated TDRs [Member] Loans that are modified as a TDR that were previously designated as a TDR Loan Restructuring Modification [Axis] Loan Restructuring Modification [Axis] Loan Restructuring Modification [Domain] Loan Restructuring Modification [Domain] Rate Interest Rate Below Market Reduction [Member] Structure Extended Maturity [Member] Financing Receivable, Modifications [Line Items] Financing Receivable, Modifications [Line Items] TDRs Financing Receivable, Modifications, Post-Modification Recorded Investment ALLL Impact Financing Receivables Impaired Troubled Debt Restructuring Allowance For Credit Losses Change Reflects the amount of the change in the allowance for credit losses related to a troubled debt restructuring. Income tax benefit from equity-based compensation expense Employee Service Share-based Compensation, Tax Benefit from Compensation Expense Intrinsic value of options exercised and RSUs that vested during the year Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Aggregate Intrinsic Value, Vested Grant date fair value of equity-based awards that vested during the year Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period, Fair Value Unrecognized compensation cost related to equity-based awards Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized Weighted-average life over which compensation cost is expected to be recognized, years Employee Service Share Based Compensation Nonvested Awards Total Compensation Cost Not Yet Recognized Period For Recognition 2 The weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, using a decimal to express in number of years. Schedule of Accounts, Notes, Loans and Financing Receivable [Table] Schedule of Accounts, Notes, Loans and Financing Receivable [Table] Nonaccrual loans Nonaccrual Financing Receivable [Member] Nonaccrual Financing Receivable [Member] Performing TDRs Performing Financial Instruments [Member] Financing Receivable [Line Items] Accounts, Notes, Loans and Financing Receivable [Line Items] Purchased loan portfolio Purchased loan portfolio Represents the dollar values of loans purchased that were not part of a business combination. Loans sold Loans sold Carrying amount of loans held for investment sold during the period Modifications that defaulted during the period that had been classified as a TDR during the previous 12 months Financing Receivable, Modifications, Subsequent Default, Recorded Investment Share Repurchase Program [Axis] Share Repurchase Program [Axis] Share Repurchase Program [Domain] Share Repurchase Program [Domain] Repurchase Plan Repurchase Plan [Member] Repurchase Plan [Member] Preferred stock, redemption period Preferred Stock, Redemption Period Preferred Stock, Redemption Period Repurchase of common stock Stock Repurchased During Period, Value Number of shares repurchased Stock Repurchased During Period, Shares Accelerated share repurchase program Accelerated Share Repurchase Program, Adjustment Common stock, remaining dollar amount authorized for repurchase Stock Repurchase Program, Remaining Authorized Repurchase Amount Other AFS securities: Available-for-sale Securities, Fair Value to Amortized Cost Basis [Abstract] Amortized Cost Available-for-sale Securities, Amortized Cost Basis Gross Unrealized Gains Available-for-sale Securities, Accumulated Gross Unrealized Gain, before Tax Gross Unrealized Losses Available-for-sale Securities, Accumulated Gross Unrealized Loss, before Tax Fair Value Available-for-sale Securities HTM securities: Held-to-maturity Securities [Abstract] Gross Unrealized Gains Held-to-maturity Securities, Accumulated Unrecognized Holding Gain Gross Unrealized Losses Held-to-maturity Securities, Accumulated Unrecognized Holding Loss Fair Value Fair Value Disclosures Fair Value Disclosures [Text Block] UPB of residential mortgage and home equity loan servicing portfolio Total Residential Mortgage Servicing Portfolio Represents the unpaid principal balance of total residential mortgage servicing portfolio. This includes the unpaid principal balances held for investment included on the balance sheet as well as the portion serviced for others representing the balances sold to third-party investors. UPB of residential mortgage loans serviced for others, primarily agency conforming fixed rate Unpaid Principal Balances Of Residential Mortgage Loans Serviced For Others Represents the unpaid principal balance of residential mortgage loans serviced for others that were previously sold to third-party investors. Mortgage loans sold with recourse Residential Mortgage Loans Sold With Recourse Represents the carrying amount of residential mortgage loans sold with recourse. Maximum recourse exposure from mortgage loans sold with recourse liability Maximum Recourse Exposure On Residential Mortgage Loans Sold Represents the total exposure to the Registrant from residential mortgage loans sold with recourse liability. Indemnification, recourse and repurchase reserves Reserve For Residential Mortgage Loans Sold Represents the reserve recorded for expected losses related to indemnification, recourse and representations & warranties residential mortgage loans sold. UPB of residential mortgage loans sold Unpaid Principal Balance Of Residential mortgage loans sold Reflects the unpaid principal balances of residential mortgage loans sold to third-party investors during the period. Pre-tax gains recognized on mortgage loans sold and held for sale Recognized Pretax Gains On Mortgage Loans With Unpaid Principal Balances Difference between the sale price and the carrying value when a financial asset transferred in a securitization or asset-backing financing arrangement is accounted for as a sale. Servicing fees recognized from mortgage loans serviced for others Bank Servicing Fees Approximate weighted average servicing fee on the outstanding balance of residential mortgage loans serviced for others Residential Mortgage Loans Weighted Average Servicing Fee Percentage Represents the weighted average servicing fee earned from servicing residential mortgage loans. The amount is presented as the percentage of fee income divided by the outstanding balances of the residential mortgage loans being serviced. Weighted average interest rate on mortgage loans serviced for others Weighted Average Interest Rate Serviced For Others Represents the weighted average interest rate on the portfolio of residential mortgage loans serviced for others. Defined Benefit Plan, Change in Benefit Obligation [Roll Forward] Defined Benefit Plan, Change in Benefit Obligation [Roll Forward] Projected benefit obligation, beginning of year Defined Benefit Plan, Benefit Obligation Actuarial (gain) loss Defined Benefit Plan, Benefit Obligation, Actuarial Gain (Loss) Benefits paid Defined Benefit Plan, Benefit Obligation, Benefits Paid Plan amendments Defined Benefit Plan, Benefit Obligation, Increase (Decrease) for Plan Amendment Acquisitions Defined Benefit Plan, Benefit Obligation, Business Combination Projected benefit obligation, end of year Accumulated benefit obligation, end of year Defined Benefit Plan, Accumulated Benefit Obligation Regulatory Requirements and Other Restrictions Regulatory Capital Requirements under Banking Regulations [Text Block] Nonperforming TDRs (also included in NPL disclosures) Nonperforming Financial Instruments [Member] Total TDRs Financing Receivable, Modifications, Recorded Investment ALLL attributable to TDRs Allowance for Credit Losses, Change in Method of Calculating Impairment Schedule of Compliance with Regulatory Capital Requirements under Banking Regulations [Table] Schedule of Compliance with Regulatory Capital Requirements under Banking Regulations [Table] Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items] Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items] CET1 Capital: Common Equity Tier One Capital [Abstract] Actual Capital, Ratio Common Equity Tier One Capital Ratio Actual Capital, Amount Common Equity Tier One Capital Capital Requirements, Minimum Common Equity Tier One Capital Required for Capital Adequacy Capital Requirements, Well-Capitalized Common Equity Tier One Capital Required to be Well-Capitalized Tier 1 Capital: Tier One Risk Based Capital [Abstract] Actual Capital, Ratio Tier One Risk Based Capital to Risk Weighted Assets Actual Capital, Amount Tier One Risk Based Capital Capital Requirements, Minimum Tier One Risk Based Capital Required for Capital Adequacy Capital Requirements, Well-Capitalized Tier One Risk Based Capital Required to be Well Capitalized Total Capital: Capital [Abstract] Actual Capital, Ratio Capital to Risk Weighted Assets Actual Capital, Amount Capital Capital Requirements, Minimum Capital Required for Capital Adequacy Capital Requirements, Well-Capitalized Capital Required to be Well Capitalized Leverage Capital: Tier One Leverage Capital [Abstract] Actual Capital, Ratio Tier One Leverage Capital to Average Assets Actual Capital, Amount Tier One Leverage Capital Capital Requirements, Minimum Tier One Leverage Capital Required for Capital Adequacy Capital Requirements, Well-Capitalized Tier One Leverage Capital Required to be Well Capitalized Schedule of Goodwill [Table] Schedule of Goodwill [Table] Residential Mortgage Banking Residential Mortgage Banking [Member] Residential Mortgage Banking [Member] Dealer Financial Services Dealer Financial Services [Member] Dealer Financial Services [Member] Specialized Lending Specialized Lending [Member] Specialized Lending [Member] Insurance Holdings Insurance Services [Member] Insurance Services [Member] Financial Services Financial Services [Member] Financial Services [Member] Goodwill [Line Items] Goodwill [Line Items] Goodwill [Roll Forward] Goodwill [Roll Forward] Goodwill, beginning balance Goodwill Acquired goodwill, net Goodwill, Acquired During Period American Coastal sale Goodwill, Written off Related to Sale of Business Unit Other adjustments Goodwill, Purchase Accounting Adjustments Goodwill, ending balance Statement [Table] Statement [Table] Parent company statement of cash flows [Line Items] Statement [Line Items] Equity in earnings of subsidiaries in excess of dividends from subsidiaries Investment in subsidiaries Payments to Acquire Interest in Subsidiaries and Affiliates Advances to subsidiaries Advances To Subsidiaries Advances To Subsidiaries Proceeds from repayment of advances to subsidiaries Repayment Of Advances To Subsidiaries Repayment Of Advances To Subsidiaries Net cash from acquisitions and divestitures Net change in long-term debt Proceeds from (Repayments of) Debt Cash dividends paid on common and preferred stock Payments of Dividends Schedule of Significant Actuarial Assumptions Used to Determine Net Periodic Pension Costs SignificantActuarialAssumptionsUsedToDetermineNetPeriodicPensionCostsTextBlock Significant Actuarial Assumptions Used To Determine Net Periodic Pension Costs [Text Block] Summary of the Components of Net Periodic Benefit Cost Recognized for Pension Plans Schedule of Net Benefit Costs [Table Text Block] Schedule of Significant Actuarial Assumptions Used to Determine Benefit Obligations Schedule of Assumptions Used [Table Text Block] Changes in Projected Benefit Obligation Schedule of Changes in Projected Benefit Obligations [Table Text Block] Changes in Fair Value of Plan Assets Schedule of Changes in Fair Value of Plan Assets [Table Text Block] Schedule of Pre-tax Amounts Recognized in AOCI Schedule of Amounts Recognized in Other Comprehensive Income (Loss) [Table Text Block] Schedule of Amounts Expected to be Amortized from AOCI Into Net Periodic Pension Cost During Next Fiscal Year Schedule of Amounts in Accumulated Other Comprehensive Income (Loss) to be Recognized over Next Fiscal Year [Table Text Block] Schedule of Estimated Future Benefit Payments Schedule of Expected Benefit Payments [Table Text Block] Schedule of Fair Value of Pension Plan Assets by Three Level Fair Value Hierarchy Schedule of Allocation of Plan Assets [Table Text Block] Measurement Basis [Axis] Measurement Basis [Axis] Fair Value Measurement [Domain] Fair Value Measurement [Domain] Portion at Fair Value Measurement [Member] Portion at Fair Value Measurement [Member] Carrying Amount Reported Value Measurement [Member] Total Fair Value Estimate of Fair Value Measurement [Member] Fair Value, Hierarchy [Axis] Fair Value, Hierarchy [Axis] Fair Value Hierarchy [Domain] Fair Value Hierarchy [Domain] Level 2 Fair Value, Inputs, Level 2 [Member] Level 3 Fair Value, Inputs, Level 3 [Member] Financial assets: Financial Instruments, Financial Assets, Balance Sheet Groupings [Abstract] HTM securities Loans and leases HFI, net of ALLL Loans and Leases Receivable, Net Amount Financial liabilities: Financial Liabilities Fair Value Disclosure [Abstract] Deposits Deposits Benefit Plans Pension and Other Postretirement Benefits Disclosure [Text Block] Schedule of Impaired Financing Receivable [Table] Schedule of Impaired Financing Receivable [Table] Financing Receivable, Impaired [Line Items] Financing Receivable, Impaired [Line Items] UPB Impaired Financing Receivable, Unpaid Principal Balance Recorded Investment Without an ALLL Impaired Financing Receivable, with No Related Allowance, Recorded Investment Recorded Investment With an ALLL Impaired Financing Receivable, with Related Allowance, Recorded Investment Related ALLL Impaired Financing Receivable, Related Allowance Average Recorded Investment Impaired Financing Receivable, Average Recorded Investment Interest Income Recognized Impaired Financing Receivable, Interest Income, Accrual Method Schedule of Fair Value, Off-balance Sheet Risks [Table] Schedule of Fair Value, Off-balance Sheet Risks [Table] Commitments to extend, originate or purchase credit Unfunded Loan Commitment [Member] Residential mortgage loans sold with recourse Loans Sold with Recourse, Residential [Member] Loans Sold with Recourse, Residential [Member] Other loans sold with recourse Loans Sold with Recourse, Other [Member] Loans Sold with Recourse, Other [Member] Letters of credit Standby Letters of Credit [Member] Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items] Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items] Notional/Contract Amount Fair Value Disclosure, Off-balance Sheet Risks, Face Amount, Liability Fair Value Fair Value Disclosure, Off-balance Sheet Risks, Amount, Liability Schedule of Commitments and Contingencies Schedule of Loss Contingencies by Contingency [Table Text Block] Schedule of Pledged Assets Pledged Assets [Table Text Block] Tabular presentation of pledged assets Commitments and Contingencies Commitments and Contingencies Disclosure [Text Block] Accumulated Other Comprehensive Income (Loss), Net of Tax [Abstract] Accumulated Other Comprehensive Income (Loss) [Table] Accumulated Other Comprehensive Income (Loss) [Table] Equity Components [Axis] Equity Components [Axis] Equity Component [Domain] Equity Component [Domain] Unrecognized Net Pension and Postretirement Costs Accumulated Defined Benefit Plans Adjustment Attributable to Parent [Member] Unrealized Net Gains (Losses) on Cash Flow Hedges Accumulated Net Gain (Loss) from Cash Flow Hedges Attributable to Parent [Member] Unrealized Net Gains (Losses) on AFS Securities Accumulated Net Investment Gain (Loss) Attributable to Parent [Member] FDIC's Share of Unrealized (Gains) Losses on AFS Securities FDIC Share on Accumulated Gain (Loss) on Available-for-Sale Securities Attributable to Parent [Member] FDIC Share on Accumulated Gain (Loss) on Available-for-Sale Securities Attributable to Parent [Member] Other, net AOCI, Other, Attributable to Parent [Member] AOCI, Other, Attributable to Parent [Member] Total AOCI Attributable to Parent [Member] Reclassification out of Accumulated Other Comprehensive Income [Axis] Reclassification out of Accumulated Other Comprehensive Income [Axis] Reclassification out of Accumulated Other Comprehensive Income [Domain] Reclassification out of Accumulated Other Comprehensive Income [Domain] Amounts reclassified from AOCI Reclassification out of Accumulated Other Comprehensive Income [Member] AOCI [Line Items] Accumulated Other Comprehensive Income (Loss) [Line Items] AOCI, net of Tax [Roll Forward] Increase (Decrease) in Stockholders' Equity [Roll Forward] Beginning balance Stockholders' Equity Attributable to Parent OCI before reclassifications, net of tax Other Comprehensive Income (Loss), before Reclassifications, Net of Tax Amounts reclassified from AOCI: Reclassification from AOCI, Current Period [Abstract] Reclassification from AOCI, Current Period [Abstract] Before tax Reclassification from AOCI, Current Period, before Tax, Attributable to Parent Tax effect Reclassification from AOCI, Current Period, Tax Amounts reclassified, net of tax Reclassification from AOCI, Current Period, Net of Tax, Attributable to Parent Total OCI, net of tax Reclassification of certain tax effects Cumulative Effect of New Accounting Principle in Period of Adoption Ending balance Schedule of Acquired Finite-Lived Intangible Asset by Major Class [Table] Schedule of Acquired Finite-Lived Intangible Asset by Major Class [Table] Finite-Lived Intangible Assets by Major Class [Axis] Finite-Lived Intangible Assets by Major Class [Axis] Finite-Lived Intangible Assets, Major Class Name [Domain] Finite-Lived Intangible Assets, Major Class Name [Domain] CDI Core Deposits [Member] Other, primarily customer relationship intangibles Other Intangible Assets [Member] Acquired Finite-Lived Intangible Assets [Line Items] Acquired Finite-Lived Intangible Assets [Line Items] Wtd. Avg. Remaining Life Acquired Finite-lived Intangible Assets, Weighted Average Useful Life Gross Carrying Amount Finite-Lived Intangible Assets, Gross Accumulated Amortization Finite-Lived Intangible Assets, Accumulated Amortization Net Carrying Amount Finite-Lived Intangible Assets, Net Schedule of Components of Income Tax Provision Schedule of Components of Income Tax Expense (Benefit) [Table Text Block] Schedule of Reconciliation Between Provision for Income Taxes and Amount Computed by Applying Federal Statutory Income Tax Rate Schedule of Effective Income Tax Rate Reconciliation [Table Text Block] Schedule of Temporary Tax Differences That Gave Rise to Deferred Tax Assets and Liabilities Schedule of Deferred Tax Assets and Liabilities [Table Text Block] Schedule of Changes in Unrecognized Tax Benefits Schedule of Unrecognized Tax Benefits Roll Forward [Table Text Block] Schedule of Financing Receivable, Allowance for Credit Losses [Table] Schedule of Financing Receivable, Allowance for Credit Losses [Table] PCI PCI [Member] Purchased credit impaired acquired and Loans Acquired from FDIC ALLL Allowance for Loan and Lease Losses [Member] RUFC ACL Allowance for Credit Loss [Member] Financing Receivable, Allowance for Credit Losses [Line Items] Financing Receivable, Allowance for Credit Losses [Line Items] Financing Receivable, Allowance for Credit Losses [Roll Forward] Financing Receivable, Allowance for Credit Losses [Roll Forward] Beginning Balance Financing Receivable, Allowance for Credit Losses Charge-Offs Allowance for Loan and Lease Losses, Write-offs Recoveries Allowance for Loan and Lease Loss, Recovery of Bad Debts Provision (Benefit) Other Allowance for Loan and Lease Losses, Adjustments, Other Ending Balance Prior service credit (cost) Defined Benefit Plan, Accumulated Other Comprehensive (Income) Loss, Prior Service Cost (Credit), before Tax Net actuarial loss Defined Benefit Plan, Accumulated Other Comprehensive Income (Loss), Gain (Loss), before Tax Net amount recognized Defined Benefit Plan, Accumulated Other Comprehensive (Income) Loss, before Tax Shareholders' Equity Stockholders' Equity Note Disclosure [Text Block] Asset Class [Axis] Asset Class [Axis] Asset Class [Domain] Asset Class [Domain] Impaired Loans Impaired Loans [Member] Impaired Loans [Member] Foreclosed Real Estate Foreclosed Real Estate [Member] Foreclosed Real Estate [Member] Measurement Frequency [Axis] Measurement Frequency [Axis] Fair Value, Measurement Frequency [Domain] Fair Value, Measurement Frequency [Domain] Nonrecurring Fair Value, Measurements, Nonrecurring [Member] Carrying Value Loans Receivable, Fair Value Disclosure Carrying Value Other Assets, Fair Value Disclosure Valuation Adjustments Fair Value, Option, Changes in Fair Value, Gain (Loss) Estimated amortization expense of identifiable intangibles Finite-Lived Intangible Assets, Net, Amortization Expense, Fiscal Year Maturity [Abstract] 2018 Finite-Lived Intangible Assets, Amortization Expense, Next Twelve Months 2019 Finite-Lived Intangible Assets, Amortization Expense, Year Two 2020 Finite-Lived Intangible Assets, Amortization Expense, Year Three 2021 Finite-Lived Intangible Assets, Amortization Expense, Year Four 2022 Finite-Lived Intangible Assets, Amortization Expense, Year Five Fair Value, by Balance Sheet Grouping [Table] Fair Value, by Balance Sheet Grouping [Table] Level 1 Fair Value, Inputs, Level 1 [Member] Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] Assets: Assets, Fair Value Disclosure [Abstract] Trading securities Trading Securities AFS securities LHFS Loans Receivable Held-for-sale, Amount MSRs Derivative assets Private equity investments Financial Instruments, Owned, Principal Investments, at Fair Value Total assets Assets, Fair Value Disclosure Liabilities: Liabilities, Fair Value Disclosure [Abstract] Derivative liabilities Securities sold short Financial Instruments Sold, Not yet Purchased, at Fair Value Total liabilities Financial and Nonfinancial Liabilities, Fair Value Disclosure Goodwill impairments Goodwill, Impairment Loss Major Types of Debt and Equity Securities [Axis] Major Types of Debt and Equity Securities [Axis] Major Types of Debt and Equity Securities [Domain] Major Types of Debt and Equity Securities [Domain] Re-REMIC Collateralized Mortgage Backed Securities [Member] Difference between fair value of Re-REMIC non-agency MBS held and the fair value of the underlying securities, percentage Fair Value, Difference Between Securities Held and Securities Owned, Percentage Fair Value, Difference Between Securities Held and the fair value of the underlying securities, Percentage Unobservable inputs, EBITDA multiples Fair Value Inputs, Earnings before Interest, Taxes, Depreciation, and Amortization Multiple Condensed Balance Sheet Statement [Table] Condensed Balance Sheet Statement [Table] Condensed Balance Sheet Statements, Captions [Line Items] Condensed Balance Sheet Statements, Captions [Line Items] Assets Assets [Abstract] Cash and due from banks Cash and Due from Banks Interest-bearing deposits with banks Interest-bearing Deposits in Banks and Other Financial Institutions AFS securities at fair value HTM securities at amortized cost Advances to / receivables from subsidiaries Due from Affiliates Investment in subsidiaries Investments in and Advances to Affiliates, Amount of Equity Other assets Other Assets Total assets Liabilities and Shareholders' Equity: Liabilities and Equity [Abstract] Short-term borrowings Short-term Debt Accounts payable and other liabilities Other Liabilities Total liabilities Liabilities Total shareholders' equity Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest Total liabilities and shareholders’ equity Liabilities and Equity Premises and Equipment Property, Plant and Equipment Disclosure [Text Block] Summary of Premises and Equipment Property, Plant and Equipment [Table Text Block] Schedule of Rent Expense Schedule of Rent Expense [Table Text Block] Schedule of Future Minimum Lease Payments for Operating Leases Schedule of Future Minimum Rental Payments for Operating Leases [Table Text Block] Operating Segments Segment Reporting Disclosure [Text Block] Statement of Financial Position [Abstract] HTM securities, fair value Preferred stock, par value per share (in usd per share) Preferred Stock, Par or Stated Value Per Share Preferred stock, liquidation preference per share (in usd per share) Preferred Stock, Redemption Price Per Share Common stock, par value per share (in usd per share) Common Stock, Par or Stated Value Per Share Cash equivalents Cash Equivalents, at Carrying Value Restricted cash Restricted Cash and Cash Equivalents HTM securities (fair value of $22,837 and $16,546 at December 31, 2017 and 2016, respectively) LHFS at fair value Loans and leases Loans and Leases Receivable, Net of Deferred Income ALLL Loans and Leases Receivable, Allowance Loans and leases, net of ALLL Premises and equipment Goodwill CDI and other intangible assets MSRs at fair value Liabilities and Shareholders’ Equity Liabilities [Abstract] Deposits: Noninterest-bearing deposits Noninterest-bearing Deposit Liabilities Interest-bearing deposits Interest-bearing Deposit Liabilities Total deposits Commitments and contingencies (Note 13) Commitments and Contingencies Shareholders’ equity: Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest [Abstract] Preferred stock, $5 par, liquidation preference of $25,000 per share Common stock, $5 par Common Stock, Value, Issued Additional paid-in capital Additional Paid in Capital Retained earnings Retained Earnings (Accumulated Deficit) AOCI, net of deferred income taxes Accumulated Other Comprehensive Income (Loss), Net of Tax Noncontrolling interests Stockholders' Equity Attributable to Noncontrolling Interest Total shareholders’ equity Common shares outstanding Common Stock, Shares, Outstanding Common shares authorized Common Stock, Shares Authorized Preferred shares outstanding Preferred Stock, Shares Outstanding Preferred shares authorized Preferred Stock, Shares Authorized Schedule of Basic and Diluted EPS Schedule of Earnings Per Share, Basic and Diluted [Table Text Block] Recorded Investment Financing Receivable, Collectively Evaluated for Impairment Related ALLL Financing Receivable, Allowance for Credit Losses, Collectively Evaluated for Impairment Pledged securities Pledged Financial Instruments, Not Separately Reported, Securities Pledged loans Pledged Assets, Not Separately Reported, Finance Receivables Document And Entity Information [Abstract] Document and Entity Information [Abstract] Document Type Document Type Amendment Flag Amendment Flag Document Period End Date Document Period End Date Entity Registrant Name Entity Registrant Name Trading Symbol Trading Symbol Entity Central Index Key Entity Central Index Key Current Fiscal Year End Date Current Fiscal Year End Date Document Fiscal Year Focus Document Fiscal Year Focus Document Fiscal Period Focus Document Fiscal Period Focus Entity Filer Category Entity Filer Category Entity Common Stock, Shares Outstanding Entity Common Stock, Shares Outstanding Entity Public Float Entity Public Float Entity Current Reporting Status Entity Current Reporting Status Entity Voluntary Filers Entity Voluntary Filers Entity Well-known Seasoned Issuer Entity Well-known Seasoned Issuer Securities Investments in Debt and Marketable Equity Securities (and Certain Trading Assets) Disclosure [Text Block] Statement of Stockholders' Equity [Abstract] Preferred Stock Preferred Stock [Member] Common Stock Common Stock [Member] Additional Paid-In Capital Additional Paid-in Capital [Member] Retained Earnings Retained Earnings [Member] AOCI Noncontrolling Interests Noncontrolling Interest [Member] Statement [Line Items] Increase (Decrease) in Stockholders' Equity [Roll Forward] Beginning balance, Shares Beginning balance OCI Stock transactions: Stock Transactions [Abstract] Stock Transactions [Abstract] Issued in business combinations, Shares Stock Issued During Period, Shares, Acquisitions Issued in business combinations Stock Issued During Period, Value, Acquisitions Issued in connection with equity awards, net, Shares Stock Issued During Period, Shares, Share-based Compensation, Net of Forfeitures Issued in connection with equity awards, net Stock Issued During Period, Value, Share-based Compensation, Net of Forfeitures Excess tax benefits in connection with equity awards Adjustment to Additional Paid in Capital, Income Tax Effect from Share-based Compensation, Net Issued in connection with preferred stock offerings Stock Issued During Period, Value, New Issues Repurchase of common stock, Shares Treasury Stock, Shares, Acquired Repurchase of common stock Treasury Stock, Value, Acquired, Par Value Method Purchase of additional ownership interest in AmRisc, LP Purchase of Additional Ownership in Subsidiary Shareholders' equity impact of purchase Of Additional Ownership Of Subsidiary Cash dividends declared on common stock Dividends, Common Stock, Cash Cash dividends declared on preferred stock Preferred Stock Dividends and Other Adjustments Equity-based compensation expense Adjustments to Additional Paid in Capital, Share-based Compensation, Requisite Service Period Recognition Reclassification of certain tax effects Tax Cuts and Jobs Act of 2017, Reclassification from AOCI to Retained Earnings Amount of increase (decrease) in accumulated other comprehensive income (AOCI) for reclassification to retained earnings of tax effect from remeasurement of deferred tax pursuant to Tax Cuts and Jobs Act of 2017. Other, net Stockholders' Equity, Other Ending balance, Shares Ending balance UPB of CRE mortgages serviced for others Unpaid Principal Balance Of Commercial Mortgage Loans Serviced For Others Represents the total unpaid principal balance of commercial real estate mortgage loans serviced by the Registrant for others. CRE mortgages serviced for others covered by recourse provisions Commercial Mortgage Loans Sold With Recourse Liability Represents the total amount of commercial real estate mortgage loans serviced for others that were covered by recourse provisions at period end. Maximum recourse exposure from CRE mortgages sold with recourse liability Maximum Recourse Exposure On Commercial Mortgage Loans Sold Represents the total exposure to the Registrant from commercial real estate mortgage loans sold with recourse liability. Recorded reserves related to recourse exposure Reserve For Commercial Mortgage Loans Sold With Recourse Represents the reserve recorded on the Registrant's books for expected losses related to commercial real estate mortgage loans sold with recourse. Originated CRE mortgages during the year Origination Of Commercial Real Estate Mortgages Represents the dollar amount of commercial real estate mortgage loans originated during the period. Computation of EPS Earnings Per Share [Text Block] Income Statement [Abstract] Interest Income Interest and Dividend Income, Operating [Abstract] Interest and fees on loans and leases Interest and Fee Income, Loans and Leases Interest and dividends on securities Interest and Dividend Income, Securities, Operating Interest on other earning assets Total interest income Interest and Dividend Income, Operating Interest Expense Interest Expense [Abstract] Interest on deposits Interest Expense, Deposits Interest on short-term borrowings Interest Expense, Short-term Borrowings Interest on long-term debt Interest Expense, Long-term Debt Total interest expense Net Interest Income Net Interest Income After Provision for Credit Losses Noninterest Income Noninterest Income [Abstract] Insurance income Insurance Commissions and Fees Service charges on deposits Fees and Commissions, Depositor Accounts Mortgage banking income Fees and Commissions, Mortgage Banking and Servicing Investment banking and brokerage fees and commissions Investment Banking, Advisory, Brokerage, and Underwriting Fees and Commissions Trust and investment advisory revenues Fees and Commissions, Fiduciary and Trust Activities Bankcard fees and merchant discounts Fees and Commissions, Credit Cards Checkcard fees Fees and Commissions, Debit Cards Operating lease income Operating Leases, Income Statement, Lease Revenue Income from bank-owned life insurance Bank Owned Life Insurance Income FDIC loss share income, net FDIC Indemnification Asset, Accretion of Discount Securities gains (losses), net Gain (Loss) on Sale of Securities, Net [Abstract] Gross realized gains Available-for-sale Securities, Gross Realized Gains Gross realized losses Available-for-sale Securities, Gross Realized Losses OTTI charges Other than Temporary Impairment Losses, Investments Non-credit portion recognized in OCI Other than Temporary Impairment Losses, Investments, Portion in Other Comprehensive Loss, before Tax, Including Portion Attributable to Noncontrolling Interest Total securities gains (losses), net Gain (Loss) on Investments Total noninterest income Noninterest Expense Noninterest Expense [Abstract] Personnel expense Labor and Related Expense Occupancy and equipment expense Occupancy, Net Software expense Information Technology and Data Processing Outside IT services Technology Services Costs Regulatory charges Federal Deposit Insurance Corporation Premium Expense Loan-related expense Loan Processing Fee Professional services Professional Fees Merger-related and restructuring charges, net Restructuring Charges Other expense Other Noninterest Expense Total noninterest expense Earnings Net Income (Loss) Attributable to Parent [Abstract] Provision for income taxes Noncontrolling interests Net Income (Loss) Attributable to Noncontrolling Interest Dividends on preferred stock Net income available to common shareholders Cash dividends declared per share (in usd per share) Common Stock, Dividends, Per Share, Declared Basic weighted average shares outstanding Diluted weighted average shares outstanding Principles of Consolidation Consolidation, Policy [Policy Text Block] Reclassifications Reclassification, Policy [Policy Text Block] Use of Estimates in the Preparation of Financial Statements Use of Estimates, Policy [Policy Text Block] Business Combinations Business Combinations Policy [Policy Text Block] Cash and Cash Equivalents; Restricted Cash Cash and Cash Equivalents, Policy [Policy Text Block] Securities Investment, Policy [Policy Text Block] LHFS Finance, Loan and Lease Receivables, Held-for-sale, Policy [Policy Text Block] Loans and Leases Receivables, Policy [Policy Text Block] NPAs Finance, Loan and Lease Receivables, Held-for-investment, Allowance and Nonperforming Loans, Nonperforming Loans Policy [Policy Text Block] ACL Financing Receivable, Allowance for Credit Losses, Policy for Uncollectible Amounts [Policy Text Block] Premises and Equipment Property, Plant and Equipment, Policy [Policy Text Block] Bank-Owned Life Insurance Life Insurance, Bank Owned, Policy [Policy Text Block] Life Insurance, Bank Owned, Policy [Policy Text Block] Income Taxes Income Tax, Policy [Policy Text Block] Derivative Financial Instruments Derivatives, Policy [Policy Text Block] Goodwill and Other Intangible Assets Goodwill and Intangible Assets, Policy [Policy Text Block] MSRs Transfers and Servicing of Financial Assets, Policy [Policy Text Block] Equity-Based Compensation Compensation Related Costs, Policy [Policy Text Block] Pension and Postretirement Benefit Obligations Pension and Other Postretirement Plans, Policy [Policy Text Block] Insurance Income Insurance Premiums Revenue Recognition, Policy [Policy Text Block] FDIC Loss Share Income FDIC Loss Share Income [Policy Text Block] FDIC Loss Share Income [Policy Text Block] Segments Segment Reporting, Policy [Policy Text Block] Changes in Accounting Principles and Effects of New Accounting Pronouncements New Accounting Pronouncements, Policy [Policy Text Block] Derivative Instrument [Axis] Income Statement Location [Axis] Income Statement Location [Axis] Income Statement Location [Domain] Income Statement Location [Domain] Interest income Interest Income [Member] Interest expense Interest Expense [Member] Other income Other Income [Member] Mortgage banking income Mortgage Banking Income [Member] Mortgage banking income [Member] Cash Flow Hedges: Pre-tax Gain (Loss) Recognized in OCI Derivative Instruments, Gain (Loss) Recognized in Other Comprehensive Income (Loss), Effective Portion, Net Pre-tax Gain (Loss) Reclassified from AOCI into Income Derivative Instruments, Gain (Loss) Reclassified from Accumulated OCI into Income, Effective Portion, Net Fair Value Hedges: Pre-tax Gain (Loss) Recognized in Income Derivative, Gain (Loss) on Derivative, Net Not Designated as Hedges: Derivative Instruments Not Designated as Hedging Instruments [Abstract] Pre-tax Gain (Loss) Recognized in Income Payment for settlement of FHA matter Loss Contingency Accrual, Payments Separate recoveries on FHA matter Loss Contingency, Receivable, Proceeds Net benefit related to FHA matter Net benefit related to FHA matter Represents the amount of the net benefit in the period related to the settlement with the FHA after consideration of recoveries and reserve adjustments. Release of mortgage repurchase reserves Release of Mortgage Repurchase Reserve Release of Mortgage Repurchase Reserve Loans and ACL Financing Receivables [Text Block] Changes In Unrecognized Tax Benefits Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward] Beginning balance of unrecognized tax benefits Unrecognized Tax Benefits Additions based on tax positions related to current year Unrecognized Tax Benefits, Increase Resulting from Current Period Tax Positions Additions (reductions) for tax positions of prior years Unrecognized Tax Benefits, Decrease Resulting from Prior Period Tax Positions Settlements Unrecognized Tax Benefits, Decrease Resulting from Settlements with Taxing Authorities Lapse of statute of limitations Unrecognized Tax Benefits, Reduction Resulting from Lapse of Applicable Statute of Limitations Unrecognized deferred tax benefits from acquisitions Unrecognized Tax Benefits, Increase Resulting from Acquisition Ending balance of unrecognized tax benefits Income Tax Contingency [Table] Income Tax Contingency [Table] Income Tax Authority [Axis] Income Tax Authority [Axis] Income Tax Authority [Domain] Income Tax Authority [Domain] Federal Domestic Tax Authority [Member] State State and Local Jurisdiction [Member] Income Tax Contingency [Line Items] Income Tax Contingency [Line Items] Unrecognized tax benefits that would have impacted effective rate if recognized Unrecognized Tax Benefits that Would Impact Effective Tax Rate Aging Analysis of Past Due Loans and Leases Past Due Financing Receivables [Table Text Block] Schedule of Credit Exposure Credit Risk Profile by Internal Loan Risk Rating, Excluding PCI Loans Financing Receivable Credit Quality Indicators [Table Text Block] Analysis of the Allowance for Credit Losses Allowance for Credit Losses on Financing Receivables [Table Text Block] Schedule of Loans Collectively Evaluated for Impairment Summary of Loans Collectively Evaluated for Impairment [Table Text Block] Summary of loans collectively evaluated for impairment [Text Block] Schedule of Loans Individually Evaluated for Impairment Impaired Financing Receivables [Table Text Block] Schedule of Performing and Nonperforming TDRs Schedule Of Performing And Nonperforming Tdrs [Table Text Block] Schedule Of Performing And Nonperforming TDRs Summary of the Primary Reason Loan Modifications Were Classified as TDRs Troubled Debt Restructurings on Financing Receivables [Table Text Block] Selected Information About Loans and Leases Selected Information About Loans and Leases [Table Text Block] Selected Information About Loans and Leases Schedule of Changes in AOCI Schedule of Accumulated Other Comprehensive Income (Loss) [Table Text Block] Weighted average assumed discount rate Defined Benefit Plan, Assumptions Used Calculating Benefit Obligation, Discount Rate Assumed rate of annual compensation increases Defined Benefit Plan, Assumptions Used Calculating Benefit Obligation, Rate of Compensation Increase Schedule of Share-based Compensation Arrangements by Share-based Payment Award [Table] Schedule of Share-based Compensation Arrangements by Share-based Payment Award [Table] Share-based Compensation Arrangement by Share-based Payment Award [Line Items] Share-based Compensation Arrangement by Share-based Payment Award [Line Items] Shares available for future grants (in thousands) Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant Vesting period Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period Option term (in years) Share-based Compensation Arrangement by Share-based Payment Award, Expiration Period AOCI Comprehensive Income (Loss) Note [Text Block] Current Financing Receivable, Recorded Investment, Current 30-89 Days Past Due Financing receivables recorded investment, thirty to eighty nine days past due Financing receivables recorded investment, thirty to eighty nine days past due 90 Days Or More Past Due Financing Receivable, Recorded Investment, 90 Days Past Due and Still Accruing Nonaccrual Financing Receivable, Recorded Investment, Nonaccrual Status Total Fair Value Loans Held-for-sale, Fair Value Disclosure Aggregate UPB Principal Amount Outstanding on Loans Held-for-sale or Securitization or Asset-backed Financing Arrangement Difference Fair Value, Option, Aggregate Differences, Loans and Long-term Receivables Award Type [Axis] Award Type [Axis] Equity Award [Domain] Equity Award [Domain] Restricted Shares/Units Restricted Stock Units (RSUs) [Member] Restricted Shares/Units Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward] Nonvested at beginning of period (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number Granted (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period Vested (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period Forfeited (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeited in Period Nonvested at end of period (in shares) Expected to vest at end of period (in shares) Expected to vest at end of period, number Restricted shares and RSUs Expected to vest at end of period, number Wtd. Avg. 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] Nonvested at beginning of period (in usd per share) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value Granted (in usd 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 Vested (in usd 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 Forfeited (in usd per share) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeitures, Weighted Average Grant Date Fair Value Nonvested at end of period (in usd per share) Expected to vest at end of period (in usd per share) Expected to vest at end of period, weighted-average grant date fair value Weighted average grant date fair value of shares/RSUs expected to vest Parent Company Condensed Balance Sheets Condensed Balance Sheet [Table Text Block] Parent Company Condensed Income and Comprehensive Income Statements Condensed Income Statement [Table Text Block] Parent Company Condensed Statements of Cash Flows Condensed Cash Flow Statement [Table Text Block] Cash and cash-equivalents Cash and Cash Equivalents [Member] U.S. equity securities International equity securities Fixed income securities Total New Accounting Pronouncements or Change in Accounting Principle [Table] New Accounting Pronouncements or Change in Accounting Principle [Table] Adjustments for New Accounting Pronouncements [Axis] Adjustments for New Accounting Pronouncements [Axis] Type of Adoption [Domain] Type of Adoption [Domain] Adjustments for New Accounting Pronouncement Adjustments for New Accounting Pronouncement [Member] New Accounting Pronouncements or Change in Accounting Principle [Line Items] New Accounting Pronouncements or Change in Accounting Principle [Line Items] Tax Cuts and Jobs Act of 2017, Reclassification from AOCI to Retained Earnings Parent Company Financial Statements Condensed Financial Information of Parent Company Only Disclosure [Text Block] Interest checking Demand Deposit Accounts Money market and savings Deposits, Money Market Deposits Time deposits Time Deposits Time deposits greater than $250,000 Time Deposits, at or Above FDIC Insurance Limit Reclassifications [Abstract] Reclassifications [Abstract] Schedule of Error Corrections and Prior Period Adjustment Restatement [Table] Schedule of Error Corrections and Prior Period Adjustment Restatement [Table] Effect of Correction Restatement Adjustment [Member] Error Corrections and Prior Period Adjustments Restatement [Line Items] Error Corrections and Prior Period Adjustments Restatement [Line Items] Net cash from operating activities Net cash from investing activities Net cash from financing activities Weighted average assumed discount rate Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Discount Rate Assumed long-term rate of annual compensation increases Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Rate of Compensation Increase Net actuarial loss Defined Benefit Plan, Expected Amortization of Gain (Loss), Next Fiscal Year Prior service credit (cost) Defined Benefit Plan, Expected Amortization of Prior Service Cost (Credit), Next Fiscal Year Net amount expected to be amortized in 2018 Defined Benefit Plan, Expected Amortization, Next Fiscal Year Internal Credit Assessment [Axis] Internal Credit Assessment [Axis] Internal Credit Assessment [Domain] Internal Credit Assessment [Domain] Pass Pass [Member] Special mention Special Mention [Member] Substandard-performing Substandard [Member] Performing Nonperforming