Defined Benefit Plan [Abstract] Change in Benefit Obligation Schedule of Defined Benefit Plans Disclosures [Table Text Block] AOCI Components Schedule of Net Periodic Benefit Cost Not yet Recognized [Table Text Block] Changes in OCI Schedule of Defined Benefit Plan Amounts Recognized in Other Comprehensive Income (Loss) [Table Text Block] Net period benefit cost for the pension and postretirement plans Schedule of Net Benefit Costs [Table Text Block] Weighted Average Benefit Assumptions Schedule of Assumptions Used [Table Text Block] Plan Asset Allocation Percentages Schedule of Allocation of Plan Assets [Table Text Block] Pension Plan Investments Schedule Of Pension Plan Investments [Table Text Block] Schedule of Fair Value of Pension Plan Assets Expected Benefit Payments Schedule of Expected Benefit Payments [Table Text Block] One Percentage Point Change in Assumed Health Care Cost Schedule of Effect of One-Percentage-Point Change in Assumed Health Care Cost Trend Rates [Table Text Block] Regulatory Capital Requirements [Abstract] Regulatory Matters Regulatory Capital Requirements under Banking Regulations [Text Block] Fair Value Disclosures [Abstract] Fair Value Measurements, Recurring and Nonrecurring [Table] Fair Value Measurements, Recurring and Nonrecurring [Table] Measurement Frequency [Axis] Measurement Frequency [Axis] Fair Value, Measurement Frequency [Domain] Fair Value, Measurement Frequency [Domain] Fair Value, Measurements, Nonrecurring Fair Value, Measurements, Nonrecurring [Member] Fair Value, Hierarchy [Axis] Fair Value, Hierarchy [Axis] Fair Value Hierarchy [Domain] Fair Value Hierarchy [Domain] Fair Value, Inputs, Level 2 Fair Value, Inputs, Level 2 [Member] Fair Value, Inputs, Level 3 Fair Value, Inputs, Level 3 [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] Assets and Liabilities Measured at Fair Value on a Non-recurring Basis Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Abstract] Commercial loans held for sale Commercial Loans Held-for-sale, Fair Value Disclosure Fair value portion of loans held-for-sale for commercial finance receivables. Provision for credit losses Provision for Credit Losses, Commercial Loans held-for-sale Provision for Credit Losses, Commercial Loans held-for-sale Mortgage loans held for sale Mortgages Held-for-sale, Fair Value Disclosure Market valuation adjustment, mortgage loans held for sale market valuation adjustment, mortgage loans held for sale A market valuation adjustment is recognized in income when the cost exceeds the estimated fair value. Impaired loans Loans Receivable, Fair Value Disclosure Provision for Credit Losses, Impaired Loans Provision for Credit Losses, Impaired Loans Provision for Credit Losses, Impaired Loans Other real estate owned Other Real Estate Owned Fair Value Disclosure Other real estate owned fair value disclosure. Foreclosure / OREO expense, net SEC Schedule III, Real Estate, Write-down or Reserve, Amount Mortgage servicing rights Servicing Asset At Amortized Value Net Net amortized carrying amount (balance) as of the balance sheet date of an asset representing net future revenues from contractually specified servicing fees, late charges, and other ancillary revenues, in excess of future costs and allowances related to servicing arrangements. Mortgage Servicing Rights (MSR) Impairment (Recovery) Mortgage Servicing Rights (MSR) Impairment (Recovery) Income Tax Disclosure [Abstract] Current and Deferred Income Tax Expense (Benefit) Schedule of Components of Income Tax Expense (Benefit) [Table Text Block] Schedule of Deferred Tax Assets and Liabilities Schedule of Deferred Tax Assets and Liabilities [Table Text Block] Summary of Valuation Allowance [Table Text Block] Summary of Valuation Allowance [Table Text Block] Schedule of Effective Income Tax Rate Reconciliation Schedule of Effective Income Tax Rate Reconciliation [Table Text Block] Summary Unrecognized Tax Benefits Schedule of Unrecognized Tax Benefits Roll Forward [Table Text Block] Closing Ratio Fair Value Inputs Closing Ratio Represents the percentage of loans currently in a lock position which management estimates will ultimately close. Weighted average discount rate Assumption for Fair Value of Assets or Liabilities that relate to Transferor's Continuing Involvement, Discount Rate Weighted average constant prepayment rate Assumption for Fair Value of Assets or Liabilities that relate to Transferor's Continuing Involvement, Prepayment Speed Income Taxes Income Tax Disclosure [Text Block] Deposits [Abstract] Time Deposits, $100,000 or More Time Deposits, $100,000 or More Time Deposits, $250,000 Or More Time Deposits, $250,000 Or More Time Deposits, $250,000 Or More Earnings Per Share [Abstract] Calculations for basic and diluted earnings per common share Earnings Per Share, Basic and Diluted [Abstract] Net income Net Income (Loss) Attributable to Parent Preferred stock dividends Preferred Stock Dividends and Other Adjustments Net income available to common equity Net Income (Loss) Available to Common Stockholders, Basic Common shareholder dividends Dividends, Common Stock Unvested share-based payment awards Unvested Share based Payment Awards Unvested Share based Payment Awards. Undistributed earnings Undistributed Earnings, Basic Undistributed earnings allocated to common shareholders Undistributed Earnings Allocated To Common Shareholders Undistributed earnings allocated to common shareholders Undistributed earnings allocated to unvested share-based payment awards Undistributed Earnings Allocated To Unvested Share Based Payment Awards Undistributed Earnings Allocated To Unvested Share-Based Payment Awards Undistributed earnings UndistributedEarningsAllocations UndistributedEarningsAllocations Basic Earnings Per Share, Basic [Abstract] Distributed earnings to common shareholders Distributed Earnings To Common Shareholders Basic Distributed earnings to common shareholders basic. Undistributed earnings allocated to common shareholders Undistributed Earnings Basic Undistributed Earnings Basic. Total common shareholders earnings, basic Common Shareholders Earnings Basic Common Shareholders Earnings Basic. Diluted Earnings Per Share, Diluted [Abstract] Distributed earnings to common shareholders Distributed Earnings To Common Shareholders Diluted Distributed earnings to common shareholders diluted. Undistributed earnings allocated to common shareholders Undistributed Earnings, Diluted Total common shareholders earnings, diluted Common Shareholders Earnings Diluted Common Shareholders Earnings Diluted. Weighted average common shares outstanding Weighted Average Number of Shares Outstanding, Basic Effect of dilutive common stock awards Incremental Common Shares Attributable to Dilutive Effect of Share-based Payment Arrangements Effect of dilutive common stock warrants Incremental Common Shares Attributable to Dilutive Effect of Call Options and Warrants Diluted weighted average common shares outstanding Weighted Average Number of Shares Outstanding, Diluted Basic earnings per common share Earnings Per Share, Basic Diluted earnings per common share Earnings Per Share, Diluted Gross deferred tax assets: Deferred Tax Assets, Gross [Abstract] Allowance for loan losses Deferred Tax Assets, Tax Deferred Expense, Reserves and Accruals, Provision for Loan Losses Allowance for other losses Deferred Tax Assets, Tax Deferred Expense, Reserves and Accruals, Other Accrued liabilities Deferred Tax Assets, Tax Deferred Expense, Reserves and Accruals, Accrued Liabilities Deferred compensation Deferred Tax Assets, Tax Deferred Expense, Compensation and Benefits Benefit of tax loss and credit carryforwards Deferred Tax Assets, Other Loss Carryforwards Nonaccrual interest Nonaccrual interest Nonaccrual interest Net unrealized losses on available-for-sale securities Other Comprehensive Income, Available-for-sale Securities, Tax Unrealized Other Comprehensive Income Available For Sale Securities Tax Unrealized Net unrealized losses on pension and postretirement benefits Other Comprehensive Income (Loss), Pension and Other Postretirement Benefit Plans, Plan Amendments, Tax Effect Unrealized Other Comprehensive Income (Loss), Pension and Other Postretirement Benefit Plans, Plan Amendments, Tax Effect Unrealized Other Deferred Tax Assets, Other Total deferred tax assets Deferred Tax Assets, Gross Valuation allowance for deferred tax assets Deferred Tax Assets, Valuation Allowance Total deferred tax assets after valuation allowance Deferred Tax Assets, Net of Valuation Allowance Gross deferred tax liabilities Deferred Tax Liabilities, Gross [Abstract] Prepaid expenses Deferred Tax Liabilities, Prepaid Expenses Goodwill Deferred Tax Liabilities, Goodwill and Intangible Assets Mortgage banking activities Deferred Tax Liabilities, Mortgage Servicing Rights Deferred loan fee income Deferred loan fee income Deferred loan fee income State deferred taxes State income taxes State income taxes Lease financing Deferred Tax Liabilities, Leasing Arrangements Bank premises and equipment DeferredTaxLiabilityDepreciation Deferred Tax Liability Deprecation Other Deferred Tax Liabilities, Other Total deferred tax liabilities Deferred Tax Liabilities, Net Net deferred tax assets Deferred Tax Assets, Net Derivative Instruments and Hedging Activities Disclosure [Abstract] Balance sheet category and fair values of derivative instruments not designated as hedging instruments Summary Of Derivative Instruments Not Designated As Hedging Instruments [Table Text Block] Summary of derivative instruments not designated as hedging instruments. Summary Of Other derivative instruments not designated as hedging instruments Summary Of Other Derivative Instruments Not Designated As Hedging Instruments [Table Text Block] [Table Text Block] Summary Of Other Derivative Instruments Not Designated As Hedging Instruments [Table Text Block] [Table Text Block] Gain (loss) on derivative instruments not designated as hedging instruments Schedule Of Derivative Instruments Gain Loss Not Designated As Hedging Instruments [Table Text Block] Schedule of derivative instruments gain loss not designated as hedging instruments. Condensed Financial Information of Parent Company Only Disclosure [Abstract] Condensed Financial Statements [Table] Condensed Financial Statements [Table] Consolidated Entities [Axis] Consolidated Entities [Axis] Consolidated Entities [Domain] Consolidated Entities [Domain] Parent Company Only Parent Company [Member] Condensed Financial Statements, Captions [Line Items] Condensed Financial Statements, Captions [Line Items] Cash Flows from Operating Activities Net Cash Provided by (Used in) Operating Activities [Abstract] Adjustments to reconcile net income to net cash provided by operating activities: Adjustments to Reconcile Net Income (Loss) to Cash Provided by (Used in) Operating Activities [Abstract] (Increase) decrease in equity in undistributed net income (loss) of subsidiaries Increase decrease in equity in undistributed net income loss of subsidiaries (Increase) decrease in equity in undistributed net income (loss) of subsidiaries Gain on sales of investment securities, net Marketable Securities, Gain (Loss) Asset (gains) losses, net Gain (Loss) on Disposition of Assets for Financial Service Operations Net change in other assets and other liabilities Increase (Decrease) in Other Operating Assets and Liabilities, Net Net cash provided by 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 Sale of Available-for-sale Securities Proceeds from Sale of Available-for-sale Securities Increase (Decrease) in Notes Receivable, Related Parties Increase (Decrease) in Notes Receivable, Related Parties Proceeds from Sale of Productive Assets Proceeds from Sale of Productive Assets Net cash used in 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 increase (decrease) in short-term funding Proceeds from (Repayments of) Short-term Debt Repayment of long-term funding Repayments of Long-term Debt Proceeds from issuance of common stock for stock-based compensation plans Proceeds from Issuance of Shares under Incentive and Share-based Compensation Plans, Including Stock Options Proceeds from issuance of preferred stock Proceeds from Issuance of Preferred Stock and Preference Stock Redemption of preferred stock Payments for Repurchase of Redeemable Preferred Stock Purchase of preferred stock Payments for Repurchase of Preferred Stock and Preference Stock Purchase of common stock returned to authorized but unissued Payments for returned to authorized but unissued common stock Purchase of treasury stock for tax withholding payments for repurchase of common stock for tax withholding The cash outflow for repurchase of common stock for tax withholding Cash dividends on common stock Payments of Ordinary Dividends, Common Stock Cash dividends on preferred stock Payments of Ordinary Dividends, Preferred Stock and Preference Stock Net cash provided by financing activities Net Cash Provided by (Used in) Financing Activities Net increase (decrease) 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 Goodwill and Intangible Assets Disclosure [Abstract] Summary of core deposit intangibles and other intangibles Schedule of Finite-Lived Intangible Assets [Table Text Block] Summary of changes in balance of mortgage servicing rights asset and mortgage servicing rights valuation allowance Summary Of Changes In Balance Of Mortgage Servicing Rights Asset And Mortgage Servicing Rights Valuation Allowance [Table Text Block] Summary of changes in balance of mortgage servicing rights asset and mortgage servicing rights valuation allowance. Summary of estimated future amortization expense Schedule of Finite-Lived Intangible Assets, Future Amortization Expense [Table Text Block] Schedule of Finite-Lived Intangible Assets [Table] Schedule of Finite-Lived Intangible Assets [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] Core Deposit Intangibles Core Deposits [Member] Other Intangibles Other Intangible Assets [Member] Finite-Lived Intangible Assets [Line Items] Finite-Lived Intangible Assets [Line Items] Summary of core deposit intangibles and other intangibles Finite-Lived Intangible Assets, Net [Abstract] Gross carrying amount Finite-Lived Intangible Assets, Gross Accumulated amortization Finite-Lived Intangible Assets, Accumulated Amortization Total Estimated Amortization Expense Finite-Lived Intangible Assets, Net Additions during the period Finite-lived Intangible Assets Acquired Amortization of other intangible assets Amortization of Intangible Assets Receivables [Abstract] Valuation and Qualifying Accounts Disclosure [Table] Valuation and Qualifying Accounts Disclosure [Table] Valuation Allowances and Reserves Type [Axis] Valuation Allowances and Reserves Type [Axis] Valuation Allowances and Reserves [Domain] Valuation Allowances and Reserves [Domain] Allowance for Unfunded Commitments Reserve for Off-balance Sheet Activities [Member] Financing Receivable, Allowance for Credit Losses [Line Items] Financing Receivable, Allowance for Credit Losses [Line Items] Change in the Allowance for Unfunded Commitments Movement in Valuation Allowances and Reserves [Roll Forward] Balance at beginning of period Valuation Allowances and Reserves, Balance Provision for Other Credit Losses Provision for Other Credit Losses Balance at end of period Property, Plant and Equipment [Abstract] Property, Plant and Equipment [Table] Property, Plant and Equipment [Table] Property, Plant and Equipment, Type [Axis] Property, Plant and Equipment, Type [Axis] Property, Plant and Equipment, Type [Domain] Property, Plant and Equipment, Type [Domain] Land Land [Member] Land improvements Land Improvements [Member] Buildings and improvements Building and Building Improvements [Member] Computers Computer Equipment [Member] Furniture, fixtures and other equipment Furniture and Fixtures [Member] Leasehold improvements Leasehold Improvements [Member] Range [Axis] Range [Axis] Range [Domain] Range [Domain] Maximum Maximum [Member] Minimum Minimum [Member] Property, Plant and Equipment [Line Items] Property, Plant and Equipment [Line Items] Property, Plant and Equipment, Net, by Type [Abstract] Property, Plant and Equipment, Net, by Type [Abstract] Estimated Useful Lives Property, Plant and Equipment, Useful Life Cost Property, Plant and Equipment, Gross Accumulated Depreciation Accumulated Depreciation, Depletion and Amortization, Property, Plant, and Equipment Net Book Value Property, Plant and Equipment, Net Schedule of Defined Benefit Plans Disclosures [Table] Schedule of Defined Benefit Plans Disclosures [Table] Fair Value, Inputs, Level 1 Fair Value, Inputs, Level 1 [Member] Defined Benefit Plan Disclosure [Line Items] Defined Benefit Plan Disclosure [Line Items] Pension Plan Investments Defined Benefit Plan, Amounts for Asset (Liability) Recognized in Statement of Financial Position [Abstract] Money market account Defined Benefit Plan Fair Value of Plan Assets Money Market Accounts Common /collective trust funds Defined Benefit Plan Fair Value of Plan Assets Mutual Funds Mutual funds Defined Benefit Plan Fair Value of Plan Assets Common/Collective Trust Funds Total Retirement Account Plan Investments Defined Benefit Plan, Fair Value of Plan Assets Schedule Of Financing Receivable Troubled Debt Restructuring [Table] Schedule Of Financing Receivable Troubled Debt Restructuring [Table] Subsequent redefault table Financing Receivable, Troubled Debt Restructuring [Axis] Class of Financing Receivable, Type of Borrower [Axis] Financing Receivable, Troubled Debt Restructuring [Domain] Class of Financing Receivable, Type of Borrower [Domain] Commercial and industrial Commercial Portfolio Segment [Member] Commercial real estate — owner occupied Commercial Real Estate Owner Occupied Portfolio [Member] Commercial real estate owner occupied residential loans Commercial real estate — investor Commercial Real Estate Investor Portfolio Segment [Member] Commercial real estate - investor loans. Real estate construction Construction Loans [Member] Residential mortgage Residential Portfolio Segment [Member] Home equity Home Equity Port Folio Segments [Member] Home equity portfolio segments. Other consumer Other consumer [Member] Installment. Financing Receivable, Modifications [Line Items] Financing Receivable, Modifications [Line Items] Number of Loans Financing Receivable, Modifications, Number of Contracts Recorded Investment Financing Receivable, Modifications, Post-Modification Recorded Investment Unpaid Principal Balance Financing Receivable, Modifications, Pre-Modification Recorded Investment Business Combinations [Abstract] Schedule of Business Acquisitions, by Acquisition [Table] Schedule of Business Acquisitions, by Acquisition [Table] Business Acquisition [Axis] Business Acquisition [Axis] Business Acquisition, Acquiree [Domain] Business Acquisition, Acquiree [Domain] Whitnell [Member] Whitnell [Member] Whitnell [Member] Bank Mutual [Member] Bank Mutual [Member] Bank Mutual [Member] Business Acquisition [Line Items] Business Acquisition [Line Items] Goodwill acquired during period Goodwill, Acquired During Period Additions to finite-lived intangible assets Number of Acquisitions Number of Acquisitions Number of Acquisitions Consideration shares transferred Business Combination, Consideration Shares Transferred Shares transferred at acquisition-date in consideration of business combination. Short-term Debt [Abstract] Schedule of Assets Sold under Agreements to Repurchase [Table] Schedule of Assets Sold under Agreements to Repurchase [Table] Repurchase Agreements and Similar Transactions, Maturity Periods [Axis] Repurchase Agreements and Similar Transactions, Maturity Periods [Axis] Repurchase Agreements and Similar Transactions, Maturity Periods [Domain] Repurchase Agreements and Similar Transactions, Maturity Periods [Domain] Overnight and Continuous Maturity Overnight and on Demand [Member] Up to 30 days Maturity Less than 30 Days [Member] 30-90 days Maturity 30 to 90 Days [Member] Greater than 90 days Maturity Greater than 90 Days [Member] Financial Instrument [Axis] Financial Instrument [Axis] Financial Instruments [Domain] Financial Instruments [Domain] Agency mortgage-related securities Mortgage-backed Securities, Issued by US Government Sponsored Enterprises [Member] Remaining Contractual Maturity of the Agreements Assets Sold under Agreements to Repurchase [Line Items] Repurchase agreements Financial Assets Sold under Agreements to Repurchase, Gross Including Not Subject to Master Netting Arrangement Short-term Funding Short-term Debt [Text Block] Schedule of Impaired Financing Receivable [Table] Schedule of Impaired Financing Receivable [Table] 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 Financing Receivable [Member] Commercial and industrial financing receivable member. Commercial and business lending Commercial And Business Lending [Member] Commercial and business lending Commercial real estate lending Commercial Real Estate Lending [Member] Commercial real estate loans Total commercial Commercial Financing Receivable [Member] Commercial financing receivable member. Residential mortgage Residential Mortgage [Member] Home equity Home Equity Line of Credit [Member] Total consumer Consumer Loan [Member] Internal Credit Assessment [Axis] Internal Credit Assessment [Axis] Internal Credit Assessment [Domain] Internal Credit Assessment [Domain] Loans with a related allowance Loans With Related Allowance [Member] Loans with a related allowance. Loans with no related allowance Loans With No Related Allowance [Member] Loans with no related allowance. Financing Receivable, Impaired [Line Items] Financing Receivable, Impaired [Line Items] Summarize of nonaccrual loans, accruing loans past due 90 days or more, and restructured loans Loan and Lease Receivables, Impaired [Abstract] Recorded Investment Impaired Financing Receivable, Recorded Investment Unpaid Principal Balance Impaired Financing Receivable, Unpaid Principal Balance Related Allowance Impaired Financing Receivable, Related Allowance Average Recorded Investment Impaired Financing Receivable, Average Recorded Investment Interest Income Recognized Impaired Financing Receivable, Interest Income, Accrual Method Net Recorded Investment of the Impaired Loans Net Recorded Investment of the Impaired Loans Net Recorded Investment of the Impaired Loans Loans and Leases Receivable, Related Parties [Roll Forward] Balance at beginning of year Loans and Leases Receivable, Related Parties New loans Loans and Leases Receivable, Related Parties, Additions Repayments Loans and Leases Receivable, Related Parties, Proceeds Changes due to status of executive officers and directors Change Due To Status of Officers And Directors Changes due to status of executive officers and directors Balance at end of year Mortgage Servicing Rights Mortgage Service Rights [Member] Mortgage service rights. Estimated future amortization expense Finite-Lived Intangible Assets, Net, Amortization Expense, Fiscal Year Maturity [Abstract] Year ending December 31, 2017 Finite-Lived Intangible Assets, Amortization Expense, Next Twelve Months Year ending December 31, 2018 Finite-Lived Intangible Assets, Amortization Expense, Year Two Year ending December 31, 2019 Finite-Lived Intangible Assets, Amortization Expense, Year Three Year ending December 31, 2020 Finite-Lived Intangible Assets, Amortization Expense, Year Four Year ending December 31, 2021 Finite-Lived Intangible Assets, Amortization Expense, Year Five Beyond 2022 Finite-Lived Intangible Assets, Amortization Expense, after Year Five Customer Relationships [Member] Customer Relationships [Member] Segments [Axis] Segments [Axis] Segments [Domain] Segments [Domain] Corporate and Commercial Specialty Commercial Banking Segment [Member] Corporate and Commercial Specialty Consolidation Items [Axis] Consolidation Items [Axis] Consolidation Items [Domain] Consolidation Items [Domain] Operating Segments Operating Segments [Member] Goodwill, Impairment Loss Goodwill, Impairment Loss Goodwill Goodwill Accounting Policies [Abstract] Finite-Lived Intangible Asset, Useful Life Finite-Lived Intangible Asset, Useful Life Retirement Benefits [Abstract] Schedule of Share-based Compensation Arrangements by Share-based Payment Award [Table] Schedule of Share-based Compensation Arrangements by Share-based Payment Award [Table] Award Type [Axis] Award Type [Axis] Equity Award [Domain] Equity Award [Domain] Performance-based Restricted Stock Award [Member] Performance-based Restricted Stock Award [Member] Performance-based Restricted Stock Award [Member] Service-based Restricted Stock Award [Member] Service-based Restricted Stock Award [Member] Service-based Restricted Stock Award [Member] Employee Stock Option [Member] Employee Stock Option [Member] Restricted Stock Award [Member] Restricted Stock Award [Member] Restricted Stock Award. Plan Name [Axis] Plan Name [Axis] Plan Name [Domain] Plan Name [Domain] 2017 Incentive Compensation Plan [Member] 2017 Incentive Compensation Plan [Member] 2017 Incentive Compensation Plan [Member] Share-based Compensation Arrangement by Share-based Payment Award [Line Items] Share-based Compensation Arrangement by Share-based Payment Award [Line Items] Vesting Period Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period Term of transfer restrictions Share-based Compensation Arrangement by Share-based Payment Award, Term of Transfer Restrictions Share-based Compensation Arrangement by Share-based Payment Award, Term of Transfer Restrictions Expiration term of awards Share-based Compensation Arrangement by Share-based Payment Award, Expiration Period Shares remaining available for grant (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant Recognized compensation expense for accelerated vesting of stock options Share-based Compensation Arrangement by Share-based Payment Award Accelerated Compensation Cost Recognized compensation expense for vesting of stock options Allocated Share-based Compensation Expense Unvested share-based payment awards Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized Employee Service Share Based Compensation Nonvested Awards Compensation Cost Not Yet Recognized Year For Recognition Employee Service Share Based Compensation Nonvested Awards Compensation Cost Not Yet Recognized Year For Recognition Employee service share based compensation nonvested awards total compensation cost not yet recognized year for recognition. Stock Based Compensation (Textuals) [Abstract] Stock Based Compensation (Textuals) [Abstract] Stock based compensation. Intrinsic value of stock options exercised InstrinsicValueOfStockOptionsExercised Intrinsic value represents the amount by which the fair market value of the underlying stock exceeds the exercise price of the stock option. Total fair value of vested stock options Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested in Period, Fair Value Short-term funding Schedule of Short-term Debt [Table Text Block] Schedule of Repurchase Agreements Schedule of Repurchase Agreements [Table Text Block] Debt Disclosure [Abstract] Long-term Funding Long-term Debt [Text Block] Summary of Significant Accounting Policies Significant Accounting Policies [Text Block] Required minimum cash and reserve balances Cash and Securities Segregated under Federal and Other Regulations Fair Value Measurements Fair Value Disclosures [Text Block] Retirement Plan Type [Axis] Retirement Plan Type [Axis] Retirement Plan Type [Domain] Retirement Plan Type [Domain] Retirement Account Plan Pension Plan [Member] Postretirement Plan Other Postretirement Benefits Plan [Member] Net period benefit cost for the pension and postretirement plans Defined Benefit Plan, Net Periodic Benefit Cost (Credit) [Abstract] Service cost Defined Benefit Plan, Service Cost Interest cost Defined Benefit Plan, Interest Cost Expected return on plan assets Defined Benefit Plan, Expected Return (Loss) on Plan Assets Prior service cost Defined Benefit Plan, Amortization of Prior Service Cost (Credit) Actuarial (gain) loss Defined Benefit Plan, Amortization of Gain (Loss) Total net pension cost Defined Benefit Plan, Net Periodic Benefit Cost (Credit) Assets Assets [Abstract] Cash and due from banks Cash and Due from Banks Investment securities available for sale, at fair value Available-for-sale Securities Notes Receivable, Related Parties, Noncurrent Notes Receivable, Related Parties, Noncurrent Investments in and receivable due from subsidiaries Investments in and Receivable Due from Subsidiaries Represents intercompany ownership interest in bank and nonbank subsidiaries Other assets Other Assets Total assets Assets Liabilities and stockholders' equity Liabilities and Equity [Abstract] Commercial paper Commercial Paper Senior notes, at par Senior Notes Subordinated notes, at par Subordinated Debt Other Long-term Debt and Capitalized Costs Other Long-term Debt and Capitalized Costs Other Long-term Debt and Capitalized Costs Total long-term funding Long-term Debt Accrued expenses and other liabilities Other Liabilities Total liabilities Liabilities Preferred equity Preferred Stock, Including Additional Paid in Capital Common equity Common Stock, Value, Issued Total stockholders’ equity Stockholders' Equity Attributable to Parent Total liabilities and stockholders’ equity Liabilities and Equity Milwaukee Center Other Segments [Member] Depreciation and amortization Depreciation Rental expense under leases Operating Leases, Rent Expense, Net Leasing income Operating Leases, Income Statement, Lease Revenue Maturities of Long-term Debt [Abstract] Maturities of Long-term Debt [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 Fair value assumptions of stock options Schedule of Share-based Payment Award, Stock Options, Valuation Assumptions [Table Text Block] Summary of Company's Stock Option Activities Share-based Compensation, Stock Options, Activity [Table Text Block] Summary of Restricted Stock Awards Activity (Excluding Salary Shares) Schedule of Share-based Compensation, Restricted Stock and Restricted Stock Units Activity [Table Text Block] Statement of Financial Position [Abstract] Stockholders’ equity Stockholders' Equity Attributable to Parent [Abstract] Preferred shares, par value Preferred Stock, Par or Stated Value Per Share Common shares, par value Common Stock, Par or Stated Value Per Share Deferred Tax Assets, Valuation Allowance [Roll Forward] Deferred Tax Assets, Valuation Allowance [Roll Forward] Deferred Tax Assets, Valuation Allowance [Roll Forward] Valuation allowance for deferred tax assets, beginning of year Increase (decrease) in current year Valuation Allowance, Deferred Tax Asset, Increase (Decrease), Amount Valuation allowance for deferred tax assets, end of year Deposits, by Type [Abstract] Deposits, by Type [Abstract] Noninterest-bearing demand deposits Noninterest-bearing Domestic Deposit, Demand Savings Deposits, Savings Deposits Interest-bearing demand Deposits, Negotiable Order of Withdrawal (NOW) Money market Deposits, Money Market Deposits Brokered CDs Brokered Certificates Of Deposit Brokered certificates of deposit. Other time Other Time Deposits Other time deposits Total deposits Deposits Deposits by type Deposits By Type [TableText Block] Deposits by type [Table Text Block] Time deposits by maturity Time Deposits By Maturity [Table Text Block] Time Deposits By Maturity [Table Text Block] Summary of Premises and Equipment Property, Plant and Equipment [Table Text Block] Minimum annual rentals and commitments under noncancelable operating leases Lessee, Operating Lease, Disclosure [Table Text Block] Long-term Funding Long-term Debt, Unclassified [Abstract] FHLB advances Advances from Federal Home Loan Banks Other Long-term Debt and Capitalized Costs Accumulated Other Comprehensive Income (Loss), Net of Tax [Abstract] Accumulated Other Comprehensive Income (Loss) Comprehensive Income (Loss) Note [Text Block] Investment securities and cash equivalents pledged as collateral Additional Collateral, Aggregate Fair Value Derivative collateral right to reclaim cash Derivative, Collateral, Right to Reclaim Cash Parent Company Only Financial Information Condensed Financial Information of Parent Company Only Disclosure [Text Block] Schedule of Assumptions for Fair Value as of Balance Sheet Date of Assets or Liabilities that relate to Transferor's Continuing Involvement [Table] Schedule of Assumptions for Fair Value as of Balance Sheet Date of Assets or Liabilities that relate to Transferor's Continuing Involvement [Table] Servicing Contracts [Member] Servicing Contracts [Member] Impaired Finance Receivable [Member] Impaired Finance Receivable [Member] Impaired Finance Receivable [Member] Valuation Technique [Axis] Valuation Technique [Axis] Valuation Technique [Domain] Valuation Technique [Domain] Discounted Cash Flow [Member] Discounted Cash Flow [Member] Discounted Cash Flow [Member] Appraisals/Discounted Cash Flow [Member] Appraisals/Discounted Cash Flow [Member] Appraisals/Discounted Cash Flow [Member] Assumption for Fair Value as of Balance Sheet Date of Assets or Liabilities that relate to Transferor's Continuing Involvement [Line Items] Assumption for Fair Value as of Balance Sheet Date of Assets or Liabilities that relate to Transferor's Continuing Involvement [Line Items] Assumption for Fair Value of Assets or Liabilities that relate to Transferor's Continuing Involvement, Discount Rate Assumption for Fair Value of Assets or Liabilities that relate to Transferor's Continuing Involvement, Prepayment Speed Earnings Per Share Textuals [Abstract] Earnings per share. Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share [Table] Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share [Table] Antidilutive Securities [Axis] Antidilutive Securities [Axis] Antidilutive Securities, Name [Domain] Antidilutive Securities, Name [Domain] Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items] Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items] Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount Assets and liabilities measured on recurring basis at fair value Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis [Table Text Block] Assets and liabilities measured at fair value using significant unobservable inputs (level 3) Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Table Text Block] Assets and liabilities measured on nonrecurring basis at fair value Fair Value Measurements, Nonrecurring [Table Text Block] Schedule of assumptions for fair value as of balance sheet date of assets or liabilities that relate to transferor's continuing involvement Schedule of Assumptions for Fair Value as of Balance Sheet Date of Assets or Liabilities that relate to Transferor's Continuing Involvement [Table Text Block] Estimated fair values of financial instruments Fair Value, by Balance Sheet Grouping [Table Text Block] Prior service cost Defined Benefit Plan Accumulated Other Comprehensive Income Net Prior Service Cost Credit Net Of Tax Net actuarial loss Defined Benefit Plan Accumulated Other Comprehensive Income Net Gains (Losses) Net Of Tax Amount not yet recognized in net periodic benefit cost, but recognized in accumulated other comprehensive loss Accumulated Other Comprehensive (Income) Loss, Defined Benefit Plan, after Tax Postretirement Plan Health Care Trend Rate [Table] Postretirement Plan Health Care Trend Rate [Table] Minimum [Member] Maximum [Member] Health Care Trend Rate by Age [Axis] Health Care Trend Rate by Age [Axis] Health Care Trend Rate [Domain] Health Care Trend Rate [Domain] Pre-65 Health Care Trend Rate [Member] Pre-65 Health Care Trend Rate [Member] Post-65 Health Care Trend [Member] Post-65 Health Care Trend [Member] Asset Allocation Porfolio Segments [Axis] Asset Allocation Porfolio Segments [Axis] Asset Allocation Portfolio Segments [Domain] Asset Allocation Portfolio Segments [Domain] Equity Securities Equity Securities [Member] Fixed income securities Debt Securities [Member] Cash and Cash Equivalents Cash and Cash Equivalents [Member] Alternative Securities Alternative Securities [Member] Retirements Plans [Line Items] Retirements Plans [Line Items] Defined Benefit Plan, Expected Amortization of Gain (Loss), Next Fiscal Year Defined Benefit Plan, Expected Amortization of Gain (Loss), Next Fiscal Year Defined Benefit Plan, Expected Amortization of Prior Service Cost (Credit), Next Fiscal Year Defined Benefit Plan, Expected Amortization of Prior Service Cost (Credit), Next Fiscal Year Employer contributions Defined Benefit Plan, Plan Assets, Contributions by Employer 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 Actual return on plan assets percentage Defined Benefit Plan Actual Return on Plan Assets Percentage Defined benefit plan actual percentage return on plan assets Defined Benefit Plan, Plan Assets, Target Allocation, Percentage Defined Benefit Plan, Plan Assets, Target Allocation, Percentage Health care trend rate assumption Defined Benefit Plan, Health Care Cost Trend Rate Assumed, Next Fiscal Year Defined Benefit Plan, Health Care Cost Trend, Reduction in Trend Rate Maximum Defined Benefit Plan, Health Care Cost Trend, Reduction in Trend Rate Maximum Defined Benefit Plan, Health Care Cost Trend, Reduction in Trend Rate Maximum Defined Benefit Plan, Health Care Cost Trend, Reduction in Trend Rate Minimum Defined Benefit Plan, Health Care Cost Trend, Reduction in Trend Rate Minimum Defined Benefit Plan, Health Care Cost Trend, Reduction in Trend Rate Ultimate future rate Defined Benefit Plan, Ultimate Health Care Cost Trend Rate Defined Benefit Plan Health Care Cost Rate Change Defined Benefit Plan Health Care Cost Rate Change Defined Benefit Plan Health Care Cost Rate Change - Actual Value From Previous Time Period Total expense related to 401(k) Defined Contribution Plan, Cost Commitments and Contingencies Disclosure [Abstract] Commitments, Off-Balance Sheet Arrangements, and Contingent Liabilities (Detail Texuals) [Table] Commitments, Off-Balance Sheet Arrangements, and Contingent Liabilities (Detail Texuals) [Table] Investment Secondary Categorization [Axis] Investment Secondary Categorization [Axis] Investments by Secondary Categorization [Domain] Investments by Secondary Categorization [Domain] UnconsolidatedProjectsLowIncomeHousing [Member] UnconsolidatedProjectsLowIncomeHousing [Member] UnconsolidatedProjectsLowIncomeHousing [Member] Low-income housing, new market tax credits projects and historic tax credit projects. PrincipalInvestmentCommitment [Member] PrincipalInvestmentCommitment [Member] PrincipalInvestmentCommitment [Member] Provided to capital based financing to private and public companies Litigation Case [Axis] Litigation Case [Axis] Litigation Case [Domain] Litigation Case [Domain] The Official Committee of Unsecured Creditors of World Marketing Chicago LLC v Associated Bank [Member] The Official Committee of Unsecured Creditors of World Marketing Chicago LLC v Associated Bank [Member] The Official Committee of Unsecured Creditors of World Marketing Chicago LLC v Associated Bank [Member] American Funds Service Company v Associated Bank [Member] American Funds Service Company v Associated Bank [Member] American Funds Service Company v Associated Bank [Member] Schumel et al. v. Bank Mutual Corporation et al., Paquin et al. v. Bank Mutual Corporation et al. [Member] Schumel et al. v. Bank Mutual Corporation et al., Paquin et al. v. Bank Mutual Corporation et al. [Member] Schumel et al. v. Bank Mutual Corporation et al., Paquin et al. v. Bank Mutual Corporation et al. [Member] Parshall et al. v. Bank Mutual Corporation et al. [Member] Parshall et al. v. Bank Mutual Corporation et al. [Member] Parshall et al. v. Bank Mutual Corporation et al. [Member] Commitments, Off-Balance Sheet Arrangements, and Contingent Liabilities (Textuals) [Line Items] Commitments, Off-Balance Sheet Arrangements, and Contingent Liabilities (Textuals) [Line Items] Commitments, Off-Balance Sheet Arrangements, and Contingent Liabilities. unfunded commitments Carrying value of investments Other Investments Commitments under unconsolidated projects Commitments Under Unconsolidated Projects Commitments under unconsolidated projects. Mortgage loan commitment Conciliation Agreement, Mortgage Loan Commitment Conciliation Agreement, Mortgage Loan Commitment Number of branch opening commitments Conciliation Agreement, Number of Branch Opening Commitments Conciliation Agreement, Number of Branch Opening Commitments Number of loan production offices Conciliation Agreement, Number of Loan Production Offices, Commitment Conciliation Agreement, Number of Loan Production Offices, Commitment Number of complaints filed under legal proceedings Number of complaints filed under legal proceedings Number of complaints filed under legal proceedings Conciliation Agreement, Commitment Term Conciliation Agreement, Commitment Term Conciliation Agreement, Commitment Term Damages sought Loss Contingency, Damages Sought, Value Damages sought, cash Loss Contingency, Damages Sought, Value, Cash Loss Contingency, Damages Sought, Value, Cash Loans repurchased under make whole requests Loans Repurchased Under Make Whole Requests Loans repurchased under make whole requests Loans sold to outside investors original amount Loans Sold To Outside Investors Original Amount Loans sold to outside investors original amount Loans sold to outside investors remaining outstanding amount Loans Sold To Outside Investors Remaining Outstanding Amount Loans sold to outside investors remaining outstanding amount Residential mortgage loans sold with recourse risk Residential Mortgage Loans Sold With Recourse Risk Residential mortgage loans sold with recourse risk. Residential mortgage loans sold with credit recourse risk Residential Mortgage Loans Sold With Credit Recourse Risk Residential mortgage loans sold with credit recourse risk. Investments, Debt and Equity Securities [Abstract] Schedule of Available-for-sale and Held-to-maturity Securities [Table] Schedule of Available-for-sale and Held-to-maturity Securities [Table] Schedule of Available-for-sale and Held-to-maturity Securities Counterparty Name [Axis] Counterparty Name [Axis] Counterparty Name [Domain] Counterparty Name [Domain] FNMA / FHLMC Fannie Mae and Freddie Mac [Member] Fannie Mae and Freddie Mac [Member] GNMA Ginnie Mae [Member] Ginnie Mae [Member] 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] U.S. Treasury securities US Treasury Securities [Member] Obligations of state and political subdivisions (municipal securities) US States and Political Subdivisions Debt Securities [Member] Residential Related Securities Residential Mortgage Backed Securities [Member] Private-label Mortgage-backed Securities, Issued by Private Enterprises [Member] GNMA commercial mortgage-related securities Commercial Mortgage Backed Securities [Member] Asset backed Securities Asset-backed Securities, Securitized Loans and Receivables [Member] Other securities (debt and equity) Other Debt And Other Equity Securities [Member] Other debt and other equity securities. Schedule of Available-for-sale and Held-to-maturity Securities [Line Items] Schedule of Available-for-sale and Held-to-maturity Securities [Table] [Line Items] [Line Items] for Schedule of Available-for-sale and Held-to-maturity Securities [Table] [Table] Investment securities available for sale Available-for-sale Securities [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 Investment securities held to maturity Held-to-maturity Securities, Balance Sheet, Reported Amounts [Abstract] Amortized Cost Held-to-maturity Securities Gross Unrealized Gains Held-to-maturity Securities, Accumulated Unrecognized Holding Gain Gross Unrealized Losses Held-to-maturity Securities, Accumulated Unrecognized Holding Loss Fair Value Held-to-maturity Securities, Fair Value Federal funds purchased Federal Funds Purchased Securities sold under agreements to repurchase Securities Sold under Agreements to Repurchase Federal funds purchased and securities sold under agreements to repurchase Federal Funds Purchased and Securities Sold under Agreements to Repurchase FHLB advances Federal Home Loan Bank, Advances, Maturities Summary, Due in Next Twelve Months Other short-term funding Other Short-term Borrowings Total short-term funding Short-term Debt Statement of Cash Flows [Abstract] Net income Provision for credit losses Provision for Loan, Lease, and Other Losses Depreciation and amortization Depreciation, Depletion and Amortization, Nonproduction Addition to (recovery of) valuation allowance on mortgage servicing rights, net Amortization of mortgage servicing rights Amortization of Mortgage Servicing Rights (MSRs) Amortization and accretion on earning assets, funding, and other, net Accretion (Amortization) of Discounts and Premiums, Investments Net amortization of tax credit investments Other Depreciation and Amortization Deferred income taxes Deferred Income Tax Expense (Benefit) Gain on mortgage banking activities, net Gain (Loss) on Sale of Mortgage Loans Mortgage loans originated and acquired for sale Payments for Origination and Purchases of Loans Held-for-sale Proceeds from sales of mortgage loans held for sale Proceeds from Sale of Mortgage Loans Held-for-sale Pension contributions Payment for Pension Benefits (Increase) decrease in interest receivable Increase (Decrease) in Accrued Interest Receivable, Net Increase (decrease) in interest payable Increase (Decrease) in Interest Payable, Net Net increase in loans Payments for (Proceeds from) Loans and Leases Purchases of Payments for Investing Activities [Abstract] Available for sale securities Payments to Acquire Available-for-sale Securities Held to maturity securities Payments to Acquire Held-to-maturity Securities Federal Home Loan Bank and Federal Reserve Bank stocks Payments to Acquire Federal Home Loan Bank Stock Premises, equipment, and software, net of disposals Payments for (Proceeds from) Productive Assets Proceeds from Proceeds from Investing Activities [Abstract] Sales of available for sale securities Sale of Federal Home Loan Bank and Federal Reserve Bank stocks Proceeds from Sale of Federal Home Loan Bank Stock Prepayments, calls, and maturities of available for sale securities Proceeds from Maturities, Prepayments and Calls of Available-for-sale Securities Prepayments, calls, and maturities of held to maturity securities Proceeds from Maturities, Prepayments and Calls of Held-to-maturity Securities Prepayments, calls and maturities of other assets Proceeds from Maturities, Prepayments and Calls of Other Investments Net change in tax credit investments Net Change in Tax Credit Investments The net cash outflow or inflow from changes in tax credit investments. Net cash (paid) received in acquisition Payments to Acquire Businesses, Net of Cash Acquired Net increase in deposits Increase (Decrease) in Deposits Repayment of long-term funding Proceeds from issuance of long-term funding Proceeds from Issuance of Long-term Debt Proceeds from issuance of common stock for stock-based compensation plans Proceeds from issuance of preferred stock Redemption of preferred stock Cash dividends on common stock Cash dividends on preferred stock Supplemental disclosures of cash flow information Supplemental Cash Flow Information [Abstract] Cash paid for interest Interest Paid, Net Cash paid for income and franchise taxes Income Taxes Paid, Net Loans and bank premises transferred to other real estate owned Real Estate Owned, Transfer to Real Estate Owned Capitalized mortgage servicing rights Servicing Asset at Fair Value, Additions Loans transferred into held for sale from portfolio, net Transfer of Portfolio Loans and Leases to Held-for-sale Supplemental Cash Flow - Acquisition Information Supplemental Cash Flow - Acquisition Information [Abstract] Supplemental Cash Flow - Acquisition Information [Abstract] Fair value of assets acquired, including cash and cash equivalents Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Assets Fair value ascribed to goodwill and intangible assets Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Intangible Assets, Including Goodwill Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Intangible Assets, Including Goodwill Fair value of liabilities assumed Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Liabilities Common stock issued in acquisition Business Combination, Consideration Transferred, Equity Interests Issued and Issuable INCOME Revenues [Abstract] Dividends from subsidiaries Cash Dividends Paid to Parent Company by Consolidated Subsidiaries Interest income on notes receivable from subsidiaries Interest and Fee Income, Loans and Leases Other income Other Operating Income Total income Revenues EXPENSE Operating Expenses [Abstract] Interest expense on short and long-term funding Interest Expense, Debt Other expense Other Expenses Total expense Operating Expenses Income before income tax expense (benefit) and equity in undistributed net income (loss) of subsidiaries Income (Loss) from Continuing Operations before Equity Method Investments, Income Taxes, Noncontrolling Interest Income tax expense Income Tax Expense (Benefit) Income before equity in undistributed net income (loss) of subsidiaries Income Loss From Continuing Operations Before Income Loss From Equity Method Investments Income Loss From Continuing Operations Before Income Loss From Equity Method Investments Equity in undistributed net income (loss) of subsidiaries Equity In Undistributed net Income (loss) of subsidiaries Equity In Undistributed net Income (loss) of subsidiaries Net income Preferred stock dividends Net income available to common equity Asset-backed Securities, Securitized Loans and Receivables [Member] Equity securities Available for Sale Available-for-sale Securities, Debt Maturities [Abstract] 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 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 Investment securities available for sale, amortized cost Ratio of Fair Value to Amortized Cost Ratio of Fair Value to Amortized Cost, AFS Ratio of Fair Value to Amortized Cost, AFS Held to Maturity Held-to-maturity Securities, Debt Maturities [Abstract] 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 Held-to-maturity Debt Securities, Amortized Cost Basis Held-to-maturity Debt Securities, Amortized Cost Basis Held-to-maturity Debt Securities, Amortized Cost Basis Amortized Cost 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 Held-to-maturity Securities, Debt Securities Held-to-maturity Securities, Debt Securities Held-to-maturity Securities, Debt Securities Total debt securities Ratio of Fair Value to Amortized Cost Ratio of Fair Value to Amortized Cost, HTM Ratio of Fair Value to Amortized Cost, HTM Schedule Of Financing Receivable Restructuring [Table] Schedule Of Financing Receivable Restructuring [Table] Financing Receivable Restructurings [Axis] Financing Receivable Restructurings [Axis] Financing Receivable Restructurings [Domain] Financing Receivable Restructurings [Domain] Financing Receivable Restructurings [Domain] Other consumer Performing Restructured Loans Performing Restructured Loans Restructured loans that are accruing Nonaccrual Restructured Loans Nonaccrual Restructured Loans Restructured loans that are on nonaccrual Held-to-maturity Securities, Sold Security, at Carrying Value Held-to-maturity Securities, Sold Security, at Carrying Value Held-to-maturity Securities, Sold Security, Realized Gain (Loss) Held-to-maturity Securities, Sold Security, Realized Gain (Loss) Available-for-sale Securities, Transferred to Held-to-maturity Securities, at Carrying Value Available-for-sale Securities, Transferred to Held-to-maturity Securities, at Carrying Value For any transfer of securities categorized as available-for-sale, this item represents the net carrying amount of the transferred security to another category of investments in debt and equity securities (trading or held-to-maturity). Investment Securities (Textuals) [Abstract] Investment Securities Textuals [Abstract] Investment securities. Proceeds from Sale of Securities Proceeds from Sale of Securities The cash inflow associated with the sale of securities that had been designated as either held-to-maturity or available-for-sale. Excludes proceeds from maturities, prepayments and calls by the issuer. Marketable Securities, Gain (Loss) Securities pledged as collateral Available-for-sale Securities Pledged as Collateral Federal Home Loan Bank Stock Federal Home Loan Bank Stock Federal Reserve Bank Stock Federal Reserve Bank Stock Net gain (loss) Other Comprehensive Income (Loss), Defined Benefit Plan, Gain (Loss), Reclassification Adjustment from AOCI, before Tax Amortization of prior service cost Other Comprehensive (Income) Loss, Defined Benefit Plan, Prior Service Cost (Credit), Reclassification Adjustment from AOCI, before Tax Amortization of actuarial loss (gain) Other Comprehensive Income (Loss), Defined Benefit Plan, Gain (Loss) Arising During Period, before Tax Plan amendments Defined Benefit Plan, Benefit Obligation, Increase (Decrease) for Plan Amendment Income tax (expense) benefit Other Comprehensive (Income) Loss, Defined Benefit Plan, after Reclassification Adjustment, Tax Other comprehensive income (loss) on pension and postretirement obligations Other Comprehensive (Income) Loss, Defined Benefit Plan, after Reclassification Adjustment, after Tax Commitments, Off-Balance Sheet Arrangements, and Contingent Liabilities Commitments and Contingencies Disclosure [Text Block] Time Deposits, Fiscal Year Maturity [Abstract] Time Deposits, Fiscal Year Maturity [Abstract] 2018 Time Deposit Maturities, Next Twelve Months 2019 Time Deposit Maturities, Year Two 2020 Time Deposit Maturities, Year Three 2021 Time Deposit Maturities, Year Four 2022 Time Deposit Maturities, Year Five Thereafter Time Deposit Maturities, after Year Five Total Time Deposits Operating Loss Carryforwards [Table] Operating Loss Carryforwards [Table] Income Tax Authority [Axis] Income Tax Authority [Axis] Income Tax Authority [Domain] Income Tax Authority [Domain] State and Local Jurisdiction State and Local Jurisdiction [Member] Internal Revenue Service (IRS) Internal Revenue Service (IRS) [Member] Operating Loss Carryforwards [Line Items] Operating Loss Carryforwards [Line Items] Valuation allowance for deferred tax assets Operating Loss Carryforwards Operating Loss Carryforwards Operating tax loss carryforwards from acquisitions Operating Loss Carryforwards By Tax Authority From Acquisitions Operating tax loss carryforwards from acquisitions Deferred Other Tax Expense (Benefit) Deferred Other Tax Expense (Benefit) Other Tax Expense (Benefit) Other Tax Expense (Benefit) Bad debt from acquired savings banks Bad Debt Reserve Of Qualified Thrift Lender Allowance for bad debt acquired from thrifts deducted from taxable income Deferred tax on bad debt from acquired savings banks No deferred tax liability for aquired allowance for bad debt from savings banks Allowance for bad debt acquired from thrifts tax liability if not deductible from taxable income Unrecognized tax benefit impact on effective tax rate Unrecognized Tax Benefits that Would Impact Effective Tax Rate Interest and penalty expense (benefit) Unrecognized Tax Benefits, Income Tax Penalties and Interest Expense Accrued interest and penalties Unrecognized Tax Benefits, Income Tax Penalties and Interest Accrued Restructured Loans Subsequent Default [Table] Restructured Loans Subsequent Default [Table] Table showing troubled debt restructuring subsequent defaults by loan type Real estate construction Number of Loans Financing Receivable, Modifications, Subsequent Default, Number of Contracts Recorded Investment Financing Receivable, Modifications, Subsequent Default, Recorded Investment Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Benefit Obligation [Abstract] Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Benefit Obligation [Abstract] Discount rate Defined Benefit Plan, Assumptions Used Calculating Benefit Obligation, Discount Rate Rate of increase in compensation levels Defined Benefit Plan, Assumptions Used Calculating Benefit Obligation, Rate of Compensation Increase Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Net Periodic Benefit Cost [Abstract] Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Net Periodic Benefit Cost [Abstract] Discount rate Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Discount Rate Rate of increase in compensation levels Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Rate of Compensation Increase Expected long-term rate of return on plan assets Income Statement [Abstract] Interest income Interest and Dividend Income, Operating [Abstract] Interest and fees on loans Interest and dividends on investment securities Interest and Dividend Income, Securities, by Taxable Status [Abstract] Taxable Interest Income, Securities, Operating, Taxable Tax-exempt Interest Income, Securities, Operating, Tax Exempt Other interest Other Interest and Dividend Income Total interest income Interest and Dividend Income, Operating Interest expense Interest Expense [Abstract] Interest on deposits Interest Expense, Deposits Interest on Federal funds purchased and securities sold under agreements to repurchase Interest Expense, Federal Funds Purchased and Securities Sold under Agreements to Repurchase Interest on other short-term funding Interest Expense, Other Short-term Borrowings Interest on long-term funding Interest Expense, Long-term Debt Total interest expense Interest Expense Net interest income Interest Income (Expense), Net Net interest income after provision for credit losses Interest Income (Expense), after Provision for Loan Loss Noninterest income Noninterest Income [Abstract] Insurance commissions and fees Insurance Commissions and Fees Service charges and deposit account fees Fees and Commissions, Depositor Accounts Card-based and loan fees Card Based And Other Nondeposit Fees Card based and other non deposit fees. Trust and asset management fees Fees and Commissions, Fiduciary and Trust Activities Brokerage commissions and fees Brokerage Commissions Revenue Mortgage banking, net Fees and Commissions, Mortgage Banking and Servicing Capital markets, net Capital Market Fees Net Capital market fees, net. Bank and corporate owned life insurance Bank and Corporate Owned Life Insurance Income Earnings on or other increases in the value of the cash surrender value of bank and corporate owned life insurance policies. Asset gains (losses), net Investment securities gains (losses), net Available-for-sale Securities, Gross Realized Gain (Loss), Excluding Other than Temporary Impairments Other Noninterest Income, Other Operating Income Total noninterest income Noninterest Income Noninterest expense Noninterest Expense [Abstract] Personnel Labor and Related Expense Occupancy Occupancy, Net Technology Information Technology and Data Processing Equipment Equipment Expense Business development and advertising Marketing and Advertising Expense Legal and professional Legal And Professional Fees Legal and professional fees. Card issuance and loan costs Loan Expense Loan Expense Foreclosure / OREO expense, net Foreclosed Real Estate Expense FDIC assessment Federal Deposit Insurance Corporation Premium Expense Other intangible amortization Other Other Noninterest Expense Total noninterest expense Noninterest Expense Income before income taxes Preferred stock dividends Earnings per common share Basic Diluted Average common shares outstanding Weighted Average Number of Shares Outstanding, Diluted [Abstract] Basic Diluted Effective Income Tax Rate Reconciliation Effective Income Tax Rate Reconciliation, Percent [Abstract] Federal income tax rate at statutory rate Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent Increases (decreases) resulting from: Increase decrease in effective income tax rate [Abstract] Tax-exempt interest and dividends Effective Income Tax Rate Reconciliation, Tax Exempt Income, Percent State income taxes (net of federal benefit) Effective Income Tax Rate Reconciliation, State and Local Income Taxes, Percent Bank owned life insurance Bank Owned Life Insurance 1 Bank owned life insurance Tax effect of tax credits and benefits, net of related expenses Effective Income Tax Rate Reconciliation, Tax Credit, Percent Tax reserve adjustments Increase (Decrease) in Tax Reserve Adjustments Increase (Decrease) in Tax Reserve Adjustments Net tax benefit from stock-based compensation Effective Income Tax Rate Reconciliation, Nondeductible Expense, Share-based Compensation Cost, Percent Tax Cuts and Jobs Act impact on deferred remeasurement Effective Income Tax Rate Reconciliation, Change in Enacted Tax Rate, Percent Other Effective Income Tax Rate Reconciliation, Other Adjustments, Percent Effective income tax rate Effective Income Tax Rate Reconciliation, Percent Document And Entity Information [Abstract] Document And Entity Information. Trading Symbol Trading Symbol Entity Registrant Name Entity Registrant Name Entity Central Index Key Entity Central Index Key Document Type Document Type Document Period End Date Document Period End Date Amendment Flag Amendment Flag Document Fiscal Year Focus Document Fiscal Year Focus Document Fiscal Period Focus Document Fiscal Period Focus Current Fiscal Year End Date Current Fiscal Year End Date Entity Well-known Seasoned Issuer Entity Well-known Seasoned Issuer Entity Voluntary Filers Entity Voluntary Filers Entity Current Reporting Status Entity Current Reporting Status Entity Filer Category Entity Filer Category Entity Public Float Entity Public Float Entity Common Stock, Shares Outstanding Entity Common Stock, Shares Outstanding Earnings Per Common Share Earnings Per Share [Text Block] Mortgage Repurchase Reserve Mortgage Repurchase Reserve [Member] Summary of changes in the residential mortgage repurchase reserve [Line Items] ValuationAndQualifyingAccoun [Line Items] Residential mortgage repurchase reserve Repurchase provision expense Valuation Allowances and Reserves, Additions for Charges to Cost and Expense Adjustments to provision expense Valuation Allowances and Reserves, Period Increase (Decrease) Charge offs, net Valuation Allowances and Reserves, Deductions Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Table] Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Table] Asset Class [Axis] Asset Class [Axis] Asset Class [Domain] Asset Class [Domain] Investment Securities Available for Sale Available-for-sale Securities [Member] Derivative Financial Instruments Derivatives [Member] Derivatives. Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] Assets and Liabilities Measured at Fair Value Using Significant Unobservable Inputs (Level 3) Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] Beginning Balance Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value Mortgage derivative gain (loss) Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Net Mortgage Derivative Gain (Loss) Included In Earnings Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Net Mortgage Derivative Gain (Loss) Included In Earnings. Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Transfers out of Level 3 Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Transfers out of Level 3 Ending Balance Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Roll Forward] Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Roll Forward] Beginning Balance Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis with Unobservable Inputs Ending Balance Operating Leases, Future Minimum Payments Due, Fiscal Year Maturity [Abstract] Operating Leases, Future Minimum Payments Due, Fiscal Year Maturity [Abstract] Payments, 2018 Operating Leases, Future Minimum Payments Due, Next Twelve Months Payments, 2019 Operating Leases, Future Minimum Payments, Due in Two Years Payments, 2020 Operating Leases, Future Minimum Payments, Due in Three Years Payments, 2021 Operating Leases, Future Minimum Payments, Due in Four Years Payments, 2022 Operating Leases, Future Minimum Payments, Due in Five Years Payments, thereafter Operating Leases, Future Minimum Payments, Due Thereafter Payments, total Operating Leases, Future Minimum Payments Due Operating Leases, Future Minimum Payments Receivable [Abstract] Operating Leases, Future Minimum Payments Receivable [Abstract] Receipts, 2018 Operating Leases, Future Minimum Payments Receivable, Current Receipts, 2019 Operating Leases, Future Minimum Payments Receivable, in Two Years Receipts, 2020 Operating Leases, Future Minimum Payments Receivable, in Three Years Receipts, 2021 Operating Leases, Future Minimum Payments Receivable, in Four Years Receipts, 2022 Operating Leases, Future Minimum Payments Receivable, in Five Years Receipts, thereafter Operating Leases, Future Minimum Payments Receivable, Thereafter Receipts, total Operating Leases, Future Minimum Payments Receivable Recent Developments Details [Abstract] Recent Developments Details [Abstract] Recent Developments [Table] Recent Developments [Table] Recent Developments [Table] Recent Developments [Line Items] Recent Developments [Line Items] [Line Items] for Recent Developments [Table] Equity [Abstract] Stockholders' Equity Note [Abstract] Stockholders' Equity Note [Abstract] Subsidiary equity balance Subsidiary Equity Balance Subsidiary Equity Balance Class Of Stock [Table] Class Of Stock [Table] information about different classes of stock Subsequent Event Type [Axis] Subsequent Event Type [Axis] Subsequent Event Type [Domain] Subsequent Event Type [Domain] Class of Stock [Axis] Class of Stock [Axis] Class of Stock [Domain] Class of Stock [Domain] Series B Preferred Stock Series B Preferred Stock [Member] Series C Preferred Stock Series C Preferred Stock [Member] Series D Preferred Stock Series D Preferred Stock [Member]