Commitments and Contingencies Disclosure [Abstract] Unrecorded Unconditional Purchase Obligation [Table] Unrecorded Unconditional Purchase Obligation [Table] Unrecorded Unconditional Purchase Obligation by Category of Item Purchased [Axis] Unrecorded Unconditional Purchase Obligation by Category of Item Purchased [Axis] Unconditional Purchase Obligation, Category of Goods or Services Acquired [Domain] Unconditional Purchase Obligation, Category of Goods or Services Acquired [Domain] Construction Contracts Construction Contracts [Member] Unrecorded Unconditional Purchase Obligation [Line Items] Unrecorded Unconditional Purchase Obligation [Line Items] Commitments to Purchase Unrecorded Unconditional Purchase Obligation Earnings Per Share [Abstract] Schedule of Earnings Per Share, Basic and Diluted [Table] Schedule of Earnings Per Share, Basic and Diluted [Table] Schedule of Earnings Per Share, Basic and Diluted [Table] Antidilutive Securities [Axis] Antidilutive Securities [Axis] Antidilutive Securities, Name [Domain] Antidilutive Securities, Name [Domain] Stock Options Employee Stock Option [Member] Unvested Restricted Stock Restricted Stock [Member] Earnings Per Share, Basic and Diluted [Line Items] Earnings Per Share, Basic and Diluted [Line Items] Earnings Per Share, Basic and Diluted [Line Items] Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount Net Income (Loss) Available to Common Stockholders, Basic Net Income (Loss) Available to Common Stockholders, Basic [Abstract] Net income Net Income (Loss) Attributable to Parent Preferred stock dividends Preferred Stock Dividends, Income Statement Impact Net income available to common stockholders Net Income (Loss) Available to Common Stockholders, Basic Weighted Average Number of Shares Outstanding, Basic and Diluted Weighted Average Number of Shares Outstanding, Basic and Diluted [Abstract] Weighted Average Number of Shares Outstanding, Basic and Diluted [Abstract] Weighted average common shares outstanding for basic earnings per share computation Weighted Average Number of Shares Outstanding, Basic Dilutive effect of stock-based compensation Incremental Common Shares Attributable to Dilutive Effect of Share-based Payment Arrangements Weighted average common shares outstanding for diluted earnings per common share computation Weighted Average Number of Shares Outstanding, Diluted Earnings Per Share, Basic and Diluted Earnings Per Share, Basic and Diluted [Abstract] Basic earnings per common share Earnings Per Share, Basic Diluted earnings per common share Earnings Per Share, Diluted Investments, Debt and Equity Securities [Abstract] Investment Securities Investments in Debt and Marketable Equity Securities (and Certain Trading Assets) Disclosure [Text Block] Document and Entity Information [Abstract] Document and Entity Information [Abstract] Statement [Table] Statement [Table] Class of Stock [Axis] Class of Stock [Axis] Class of Stock [Domain] Class of Stock [Domain] Class A Common Stock Common Class A [Member] Class B Common Stock Common Class B [Member] Statement [Line Items] Statement [Line Items] Entity Registrant Name Entity Registrant Name Entity Central Index Key Entity Central Index Key Current Fiscal Year End Date Current Fiscal Year End Date Entity Filer Category Entity Filer Category Document Type Document Type Document Period End Date Document Period End Date Document Fiscal Year Focus Document Fiscal Year Focus Document Fiscal Period Focus Document Fiscal Period Focus Amendment Flag Amendment Flag Entity Common Stock, Shares Outstanding Entity Common Stock, Shares Outstanding Statement of Financial Position [Abstract] Investment securities: Held-to-maturity Securities, Parenthetical Disclosure [Abstract] Held-to-maturity, fair values Held-to-maturity Securities, Fair Value Stockholders' equity: Stockholders' Equity, Number of Shares, Par Value and Other Disclosures [Abstract] Nonvoting noncumulative preferred stock, par value Preferred Stock, No Par Value Nonvoting noncumulative preferred stock, authorized shares Preferred Stock, Shares Authorized Nonvoting noncumulative preferred stock, issued shares Preferred Stock, Shares Issued Nonvoting noncumulative preferred stock, outstanding shares Preferred Stock, Shares Outstanding Receivables [Abstract] Schedule of Financing Receivables Past Due [Table] Schedule of Financing Receivables Past Due [Table] Class of Financing Receivable [Axis] Class of Financing Receivable [Axis] Class of Financing Receivable [Domain] Class of Financing Receivable [Domain] Commercial real estate Commercial Real Estate Other Receivable [Member] Land acquisition & development construction real estate Land Acquisition & Development Construction Financing Receivable [Member] Land Acquisition & Development Construction Financing Receivable [Member] Residential construction real estate Residential Real Estate Construction Financing Receivable [Member] Residential Real Estate Construction Financing Receivable [Member] Commercial construction real estate Commercial Real Estate Construction Financing Receivable [Member] Total construction loans Real Estate Construction Financing Receivable [Member] Real Estate Construction Financing Receivable [Member] Residential real estate Residential Mortgage [Member] Agricultural real estate Agricultural Real Estate Financing Receivable [Member] Agricultural Real Estate Financing Receivable [Member] Total real estate loans Real Estate Financing Receivable [Member] Real Estate Financing Receivable [Member] Indirect consumer Consumer Indirect Financing Receivable [Member] Consumer Indirect Financing Receivable [Member] Other consumer Consumer Other Financing Receivable [Member] Credit card consumer Consumer Credit Card Financing Receivable [Member] Total consumer loans Consumer Financing Receivable [Member] Consumer Financing Receivable [Member] Commercial Commercial Financing Receivable [Member] Commercial Financing Receivable [Member] Agricultural Agricultural Financing Receivable [Member] Agricultural Financing Receivable [Member] Other, including overdrafts Other Financing Receivable, Including Overdrafts [Member] Other Financing Receivable, Including Overdrafts [Member] Loans held for investment Loans and Leases Held for Investment [Member] Loans and Leases Held for Investment [Member] Mortgage loans originated for sale Mortgage Loans Held for Sale [Member] Mortgage Loans Held for Sale [Member] Total loans Loans and Leases Receivable [Member] Loans and Leases Receivable [Member] Loans and Leases Receivable Recorded Investment, Past Due [Line Items] Financing Receivable, Recorded Investment, Past Due [Line Items] 30 to 59 Days Past Due Financing Receivable, Recorded Investment, 30 to 59 Days Past Due 60 to 89 Days Past Due Financing Receivable, Recorded Investment, 60 to 89 Days Past Due Greater than 90 Days Past Due Financing Receivable, Recorded Investment, Equal to Greater than 90 Days Past Due Total Loans 30 or More Days Past Due Financing Receivable, Recorded Investment, Past Due Current Loans Financing Receivable, Recorded Investment, Current Non-accrual Loans Financing Receivable, Recorded Investment, Nonaccrual Status Loans held for investment Loans And Leases Receivable Held For Investment Gross carrying amount of all categories of loans and leases held in the portfolio, excluding loans held for sale. Mortgage loans held for sale Loans Held-for-sale, Mortgages Total loans Loans and Leases Receivable, Gross Interest Income on Non-Accrual Loans if Accrued Financing Receivable, Recorded Investment, Nonaccrual Status, Interest Income if Accrued Financing Receivable, Recorded Investment, Nonaccrual Status, Interest Income if Accrued Repossessed Assets [Abstract] Other Real Estate Owned Real Estate Owned [Text Block] Statement of Stockholders' Equity [Abstract] Statement, Equity Components [Axis] Equity Components [Axis] Equity Component [Domain] Equity Component [Domain] Preferred stock Preferred Stock Including Additional Paid in Capital [Member] Common stock Common Stock Including Additional Paid in Capital [Member] Retained earnings Retained Earnings [Member] Accumulated other comprehensive income Accumulated Other Comprehensive Income (Loss) [Member] Increase (Decrease) in Stockholders' Equity [Roll Forward] Increase (Decrease) in Stockholders' Equity [Roll Forward] Beginning Balance Stockholders' Equity Attributable to Parent Comprehensive income: Comprehensive Income (Loss), Net of Tax, Attributable to Parent [Abstract] Net income Other comprehensive income, net of tax Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent Common stock transactions: Common Stock Transactions [Abstract] Common Stock Transactions. Common shares purchased and retired 25,677 and 17,981 in 2013 and 2012 respectively Stock Repurchased and Retired During Period, Value Common shares issued 26,096 and 23,973 in 2013 and 2012 respectively Stock Issued During Period, Value, New Issues Non-vested common shares issued 108,873 and 122,912 in 2013 and 2012 respectively Stock Issued During Period, Value, Restricted Stock Award, Gross 10,318 and 3,193 non-vested common shares forfeited in 2013 and 2012 respectively Stock Issued During Period, Value, Restricted Stock Award, Forfeitures 446,404 and 118,865 stock options exercised, net of 150,290 and 39,667 shares tendered in payment of option price and income tax withholding amounts in 2013 and 2012 respectively Stock Issued During Period, Value, Stock Options Exercised Tax benefit of stock-based compensation Adjustments to Additional Paid in Capital, Income Tax Benefit from Share-based Compensation Stock-based compensation expense Adjustments to Additional Paid in Capital, Share-based Compensation, Requisite Service Period Recognition Cash dividends declared: Dividends [Abstract] Common ($.13) and ($0.24) per share in 2013 and 2012 repectively Dividends, Common Stock, Cash Preferred (6.75%) per share in 2012 Dividends, Preferred Stock, Cash Ending Balance Schedule of Financing Receivable, Allowance for Credit Losses [Table] Schedule of Financing Receivable, Allowance for Credit Losses [Table] Real Estate Real Estate Portfolio Segment [Member] Real Estate Portfolio Segment [Member] Consumer Consumer Portfolio Segment [Member] Commercial Commercial Portfolio Segment [Member] Agriculture Agriculture Portfolio Segment [Member] Agriculture Portfolio Segment [Member] Other Other Portfolio Segment [Member] Other Portfolio Segment [Member] Financing Receivable, Allowance for Credit Losses [Line Items] Financing Receivable, Allowance for Credit Losses [Line Items] Allowance for Loan and Lease Losses [Roll Forward] Allowance for Loan and Lease Losses [Roll Forward] Beginning balance Loans and Leases Receivable, Allowance Provision charged to operating expense Provision for Loan and Lease Losses Less loans charged-off Allowance for Loan and Lease Losses, Write-offs Add back recoveries of loans previously charged-off Allowance for Loan and Lease Loss, Recovery of Bad Debts Ending balance Financing Receivable, Allowance for Credit Loss, Additional Information [Abstract] Financing Receivable, Allowance for Credit Loss, Additional Information [Abstract] Allowance for loan losses: Loans and Leases Receivable, Allowance [Abstract] Loans individually evaluated for impairment Financing Receivable, Allowance for Credit Losses, Individually Evaluated for Impairment Loans collectively evaluated for impairment Financing Receivable, Allowance for Credit Losses, Collectively Evaluated for Impairment Ending balance Total loans: Loans and Leases Receivable Disclosure [Abstract] Individually evaluated for impairment Financing Receivable, Individually Evaluated for Impairment Individually evaluated for impairment Financing Receivable, Collectively Evaluated for Impairment Total loans Organization, Consolidation and Presentation of Financial Statements [Abstract] Basis of Presentation Business Description and Basis of Presentation [Text Block] Banking and Thrift [Abstract] Schedule of Compliance with Regulatory Capital Requirements under Banking Regulations Schedule of Compliance with Regulatory Capital Requirements under Banking Regulations [Table Text Block] Loans Financing Receivables [Text Block] Other Real Estate Owned Roll Forward Real Estate Acquired Through Foreclosure, Roll Forward [Table Text Block] Real Estate Acquired Through Foreclosure, Roll Forward [Table Text Block] Schedule of Accounts, Notes, Loans and Financing Receivable [Table] Schedule of Accounts, Notes, Loans and Financing Receivable [Table] Loans and Leases Receivable [Line Items] Accounts, Notes, Loans and Financing Receivable [Line Items] Loans held for investment Fair Value Disclosures [Abstract] Fair Value Measurements Fair Value Disclosures [Text Block] Allowance For Loan Losses Allowance for Credit Losses [Text Block] Equity [Abstract] Net accumulated other comprehensive income: Accumulated Other Comprehensive Income (Loss), Net of Tax [Abstract] Net unrealized gain on investment securities available-for-sale Accumulated Other Comprehensive Income (Loss), Available-for-sale Securities Adjustment, Net of Tax Net actuarial loss on defined benefit post-retirement benefit plans Defined Benefit Plan, Accumulated Other Comprehensive Income Net Gains (Losses), after Tax Net accumulated other comprehensive income Accumulated Other Comprehensive Income (Loss), Net of Tax Statement, Scenario [Axis] Scenario [Axis] Scenario, Unspecified [Domain] Scenario, Unspecified [Domain] Assets Assets [Abstract] Cash and due from banks Cash and Due from Banks Federal funds sold Federal Funds Sold Interest bearing deposits in banks Interest-bearing Deposits in Banks and Other Financial Institutions Total cash and cash equivalents Cash, Cash Equivalents, and Federal Funds Sold Investment securities: Marketable Securities [Abstract] Available-for-sale Available-for-sale Securities, Debt Securities Held-to-maturity (estimated fair values of $199,078 and $161,877 at September 30, 2012 and December 31, 2011, respectively) Held-to-maturity Securities Total investment securities Marketable Securities Loans held for investment Mortgage loans held for sale Less allowance for loan losses Net loans Loans and Leases Receivable, Net Amount Premises and equipment, net of accumulated depreciation Property, Plant and Equipment, Net Goodwill Goodwill Company-owned life insurance Bank Owned Life Insurance Other real estate owned (OREO) Real Estate Acquired Through Foreclosure Accrued interest receivable Interest Receivable Mortgage servicing rights, net of accumulated amortization and impairment reserve Servicing Asset at Amortized Cost Deferred tax asset, net Deferred Tax Assets, Net of Valuation Allowance Core deposit intangibles, net of accumulated amortization Core Deposit Intangibles Net Core deposit intangibles, net of accumulated amortization. Other assets Other Assets Total assets Assets Liabilities and Stockholders' Equity Liabilities and Equity [Abstract] Deposits: Deposits [Abstract] Non-interest bearing Noninterest-bearing Deposit Liabilities Interest bearing Interest-bearing Deposit Liabilities Total deposits Deposits Securities sold under repurchase agreements Securities Sold under Agreements to Repurchase Accounts payable and accrued expenses Accounts Payable and Accrued Liabilities Accrued interest payable Interest Payable Long-term debt Other Long-term Debt Other borrowed funds Other Short-term Borrowings Preferred stock pending redemption Preferred Stock, Pending Redemption Preferred Stock, Pending Redemption Subordinated debentures held by subsidiary trusts Junior Subordinated Debenture Owed to Unconsolidated Subsidiary Trust Total liabilities Liabilities Stockholders' equity: Stockholders' Equity Attributable to Parent [Abstract] Nonvoting noncumulative preferred stock without par value; authorized 100,000 shares; issued and outstanding 5,000 shares as of March 31, 2012 and December 31, 2011 Preferred Stock, Including Additional Paid in Capital Common stock Common Stocks, Including Additional Paid in Capital Retained earnings Retained Earnings (Accumulated Deficit) Accumulated other comprehensive income, net Total stockholders' equity Total liabilities and stockholders' equity Liabilities and Equity Schedule of Stock by Class [Table] Schedule of Stock by Class [Table] Series A Preferred Stock [Member] Series A Preferred Stock [Member] Class of Stock [Line Items] Class of Stock [Line Items] Common Stock, Shares, Outstanding Common Stock, Shares, Outstanding Preferred Stock, Aggregate Redemption Price Preferred Stock, Aggregate Redemption Price Preferred Stock, Aggregate Redemption Price Change in net unrealized Gain during period: Other Comprehensive Income (Loss), Available-for-sale Securities Adjustment, before Reclassification Adjustments, Net of Tax [Abstract] Change in net unrealized gain during period, before tax amount Other Comprehensive Income (Loss), Unrealized Holding Gain (Loss) on Securities Arising During Period, before Tax Change in net unrealized gain during period, tax expense (benefit) Other Comprehensive Income (Loss), Unrealized Holding Gain (Loss) on Securities Arising During Period, Tax Change in net unrealized gain during period, net of tax amount Other Comprehensive Income (Loss), Unrealized Holding Gain (Loss) on Securities Arising During Period, Net of Tax Reclassification adjustment for gains included in net income: Other Comprehensive Income (Loss), Available-for-sale Securities Adjustment, Net of Tax [Abstract] Reclassification adjustment for gains included in net income, before tax amount Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI for Sale of Securities, before Tax Reclassification adjustment for gains included in net income, tax expense (benefit) Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI for Sale of Securities, Tax Reclassification adjustment for gains included in net income, net of tax amount Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI for Sale of Securities, Net of Tax Change in net actuarial loss: Other Comprehensive (Income) Loss, Pension and Other Postretirement Benefit Plans, Adjustment, Net of Tax [Abstract] Change in net actuarial loss, before tax amount Other Comprehensive (Income) Loss, Pension and Other Postretirement Benefit Plans, Adjustment, before Tax Change in net actuarial loss, tax expense (benefit) Other Comprehensive Income (Loss), Pension and Other Postretirement Benefit Plans, Adjustment, Tax Other Comprehensive Income (Loss), Pension and Other Postretirement Benefit Plans, Adjustment, Tax Change in net actuarial loss, net of tax amount Other Comprehensive (Income) Loss, Pension and Other Postretirement Benefit Plans, Adjustment, Net of Tax Other comprehensive income (loss): Other Comprehensive Income (Loss), Net of Tax [Abstract] Other comprehensive income (loss), before tax Other Comprehensive Income (Loss), before Tax Total other comprehensive income, tax expense (benefit) Other Comprehensive Income (Loss), Tax Total other comprehensive income, net of tax amount Other Comprehensive Income (Loss), Net of Tax Schedule of Financing Receivable, Recorded Investment, Credit Quality Indicator [Table] Schedule of Financing Receivable, Recorded Investment, Credit Quality Indicator [Table] Credit Quality Indicator [Axis] Internal Credit Assessment [Axis] Internal Credit Assessment [Domain] Internal Credit Assessment [Domain] Other Assets Especially Mentioned Special Mention [Member] Substandard Substandard [Member] Doubtful Doubtful [Member] Total Criticized Loans Total Criticized Loans [Member] Total Criticized Loans [Member] Loans and Leases Receivable Recorded Investment, Criticized Loans [Line Items] Financing Receivable, Recorded Investment [Line Items] Computation of Basic and Diluted Earnings per Share Schedule of Earnings Per Share, Basic and Diluted [Table Text Block] Regulatory Capital Regulatory Capital Requirements under Banking Regulations [Text Block] Common Stock Stockholders' Equity Note Disclosure [Text Block] 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 provided by operating activities: Adjustments to Reconcile Net Income (Loss) to Cash Provided by (Used in) Operating Activities [Abstract] Provision for loan losses Provision for Loan Losses Expensed Net (gain) loss on disposal of property and equipment Gain (Loss) on Disposition of Property Plant Equipment Depreciation and amortization Depreciation, Depletion and Amortization Net premium amortization on investment securities Accretion (Amortization) of Discounts and Premiums, Investments Net gains on investment securities transactions Gain (Loss) on Sale of Debt Investments Net gains on sales of mortgage loans held for sale Gain (Loss) on Sale of Loans and Leases Net gain on sale of OREO Gains (Losses) on Sales of Other Real Estate OREO valuation adjustments Asset Impairment Charges Net impairment (reversal of impairment) of mortgage servicing rights Mortgage Servicing Rights (MSR) Impairment (Recovery) Gain Loss on Sale of Mortgage Servicing Gain Loss on Sale of Mortgage Servicing Gain Loss on Sale of Mortgage Servicing Deferred income tax expense Deferred Income Tax Expense (Benefit) Net increase in cash surrender value of company-owned life insurance policies Life Insurance, Corporate or Bank Owned, Change in Value Stock-based compensation expense Share-based Compensation Tax benefits from stock-based compensation expense Deferred Tax Expense from Stock Options Exercised Excess tax benefits from stock-based compensation Excess Tax Benefit from Share-based Compensation, Operating Activities Originations of mortgage loans held for sale, net of sales Increase (Decrease) in Mortgage Loans Held-for-sale Changes in operating assets and liabilities: Increase (Decrease) in Operating Capital [Abstract] Increase in interest receivable Increase (Decrease) in Accrued Interest Receivable, Net Decrease in other assets Increase (Decrease) in Other Operating Assets Decrease in accrued interest payable Increase (Decrease) in Interest Payable, Net Decrease in accounts payable and accrued expenses Increase (Decrease) in Accounts Payable and Accrued Liabilities 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] Purchases of held-to-maturity investment securities Payments to Acquire Held-to-maturity Securities Purchases of available-for-sale investment securities Payments to Acquire Available-for-sale Securities Proceeds from maturities and paydowns of held-to-maturity investment securities Proceeds from Sale and Maturity of Held-to-maturity Securities Proceeds from maturities and paydowns of available-for-sale investment securities Proceeds from Sale and Maturity of Available-for-sale Securities Capital distribution by unconsolidated subsidiary trust Proceeds from Equity Method Investment, Dividends or Distributions, Return of Capital Proceeds from sales of mortgage servicing rights Payments for (Proceeds from) Mortgage Servicing Rights Extensions of credit to customers, net of repayments Payments for (Proceeds from) Other Loans and Leases Recoveries of loans charged-off Proceeds from Recoveries of Loans Previously Charged off Proceeds from sales of OREO Proceeds from Sale of Wholly Owned Real Estate and Real Estate Acquired in Settlement of Loans Capital contribution to unconsolidated equity method investee Payments for (Proceeds from) 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 deposits Increase (Decrease) in Deposits Net decrease in repurchase agreements Proceeds from (Payments for) in Securities Sold under Agreements to Repurchase Net increase (decrease) in short-term borrowings Proceeds from (Repayments of) Short-term Debt Repayment of junior subordinated debentures held by subsidiary trusts Repayments of Subordinated Debt Repayments of long-term debt Repayments of Other Long-term Debt Redemption of preferred stock Payments for Repurchase of Preferred Stock and Preference Stock Proceeds from issuance of common stock Proceeds from Issuance of Common Stock Excess tax benefits from stock-based compensation Excess Tax Benefit from Share-based Compensation, Financing Activities Purchase and retirement of common stock Payments for Repurchase of Common Stock Dividends paid to common stockholders Payments of Ordinary Dividends, Common Stock Dividends paid to preferred stockholders Payments of Ordinary Dividends, Preferred Stock and Preference Stock Net cash provided by (used in) 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 Supplemental disclosures of cash flow information: Supplemental Cash Flow Information [Abstract] Cash paid during the period for income taxes Income Taxes Paid Cash paid during the period for interest expense Interest Paid Other Comprehensive Income Comprehensive Income (Loss) [Table Text Block] Amortized Cost and Approximate Fair Values of Investment Securities Marketable Securities [Table Text Block] Realized Gains (Losses) on Investments Realized Gain (Loss) on Investments [Table Text Block] Gross Unrealized Losses and Fair Values of Investment Securities Schedule of Unrealized Loss on Investments [Table Text Block] Maturities of Investment Securities Investments Classified by Contractual Maturity Date [Table Text Block] Income Statement [Abstract] Interest income: Interest Income (Expense), Net [Abstract] Interest and fees on loans Interest and Fee Income, Loans and Leases Interest and dividends on investment securities: Interest and Dividend Income, Operating [Abstract] Taxable Interest Income, Securities, Operating, Taxable Exempt from federal taxes Interest Income, Securities, Operating, Tax Exempt Interest on deposits in banks Interest Income, Domestic Deposits Interest on federal funds sold Interest Income, Federal Funds Sold Total interest income Interest and Dividend Income, Operating Interest expense: Interest Expense [Abstract] Interest on deposits Interest Expense, Deposits Interest on securities sold under repurchase agreements Interest Expense, Securities Sold under Agreements to Repurchase Interest on long-term debt Interest Expense, Other Long-term Debt Interest on preferred stock pending redemption Interest Expense, Preferred Stock Pending Redemption Interest Expense, Preferred Stock Pending Redemption Interest on subordinated debentures held by subsidiary trusts Interest Expense, Junior Subordinated Debentures Total interest expense Interest Expense Net interest income Interest Income (Expense), Net Provision for loan losses Net interest income after provision for loan losses Interest Income (Expense), after Provision for Loan Loss Non-interest income: Noninterest Income [Abstract] Income from the origination and sale of loans Income From Origination And Sale Of Loans Income from origination and sale of loans. Other service charges, commissions and fees Fees and Commissions, Other Investment Advisory, Management and Administrative Fees Investment Advisory, Management and Administrative Fees Service charges on deposit accounts Fees and Commissions, Depositor Accounts Investment securities gains, net Other income Noninterest Income, Other Operating Income Total non-interest income Noninterest Income Non-interest expense: Noninterest Expense [Abstract] Salaries and wages Labor and Related Expense Employee benefits Other Labor-related Expenses Occupancy, net Occupancy, Net Furniture and equipment Equipment Expense Outsourced technology services Outsourced Technology Services Outsourced technology services. OREO expense, net of income Other Real Estate Owned Expense Net Of Income Other Real Estate Owned expense net of income. FDIC insurance premiums Federal Deposit Insurance Corporation Premium Expense Professional fees Professional Fees Mortgage servicing rights amortization Amortization of Mortgage Servicing Rights (MSRs) Mortgage servicing rights impairment recovery Core deposit intangibles amortization Amortization of Intangible Assets Other expenses Other Noninterest Expense Total non-interest expense Noninterest Expense Income before income tax expense Income (Loss) from Continuing Operations before Income Taxes, Extraordinary Items, Noncontrolling Interest Income tax expense Income Tax Expense (Benefit) Net income Preferred stock dividends Net income available to common stockholders Basic earnings per common share Diluted earnings per common share Schedule of Allowance for Loan Losses by Portfolio Segment Allowance for Credit Losses on Financing Receivables [Table Text Block] Transferred Loans to OREO SEC Schedule III, Real Estate, Acquisitions Through Foreclosures Transferred Loans to Mortgage Servicing Assets Transfer of Portfolio Loans to Mortgage Servicing Assets Transfer of Portfolio Loans to Mortgage Servicing Assets Transfer from Investments Transfer from Investments Fair Value Measurements, Recurring and Nonrecurring [Table] Fair Value Measurements, Recurring and Nonrecurring [Table] Fair Value, by Balance Sheet Grouping, Disclosure Item Amounts [Axis] Measurement Basis [Axis] Fair Value, Disclosure Item Amounts [Domain] Fair Value Measurement [Domain] Estimated Fair Value Estimate of Fair Value Measurement [Member] Carrying Amount Reported Value Measurement [Member] Debt Security [Axis] Debt Security [Axis] Major Types of Debt Securities [Domain] Major Types of Debt Securities [Domain] Obligations of U.S. government agencies US Government Agencies Debt Securities [Member] U.S. agency residential mortgage-backed securities & collateralized mortgage obligations Mortgage-backed Securities, Issued by US Government Sponsored Enterprises [Member] Private mortgage-backed securities Mortgage-backed Securities, Issued by Private Enterprises [Member] Fair Value, Hierarchy [Axis] Fair Value, Hierarchy [Axis] Fair Value, Measurements, Fair Value Hierarchy [Domain] Fair Value Hierarchy [Domain] Quoted Prices in Active Markets for Identical Assets (Level 1) Fair Value, Inputs, Level 1 [Member] Significant Other Observable Inputs (Level 2) Fair Value, Inputs, Level 2 [Member] Significant Unobservable Inputs (Level 3) Fair Value, Inputs, Level 3 [Member] Change During Period Changes Measurement [Member] Measurement Frequency [Axis] Measurement Frequency [Axis] Fair Value, Measurement Frequency [Domain] Fair Value, Measurement Frequency [Domain] Fair Value Measured on a Recurring Basis Fair Value, Measurements, Recurring [Member] Fair Value Measured on a Non-recurring Basis Fair Value, Measurements, Nonrecurring [Member] Other Real Estate Owned Expense, Type [Axis] Other Real Estate Owned Expense, Type [Axis] Other Real Estate Owned Expense, Type [Axis] Other Real Estate Owned Expense, Type [Domain] Other Real Estate Owned Expense, Type [Domain] Other Real Estate Owned Expense, Type [Domain] Directly Related to Receipt of Updated Appraisals and Adjustments Directly Related to Receipt of Updated Appraisals and Adjustments [Member] Directly Related to Receipt of Updated Appraisals and Adjustments [Member] Based on Management Estimates of the Current Fair Value of Properties Based on Management Estimates of the Current Fair Value of Properties [Member] Based on Management Estimates of the Current Fair Value of Properties [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] Investment securities available-for-sale Available-for-sale Securities Mortgage servicing rights Servicing Asset at Fair Value, Amount Impaired loans Loans Receivable, Impaired, Fair Value Disclosure Loans Receivable, Impaired, Fair Value Disclosure Other real estate owned Real Estate Acquired Through Foreclosure, Fair Value Disclosure Real Estate Acquired Through Foreclosure, Fair Value Disclosure Long-lived assets to be disposed of by sale Assets Held-for-sale, Long Lived, Fair Value Disclosure Related Allowance Impaired Financing Receivable, Related Allowance Impaired Financing Receivable, Related Allowance, Partial Loan Charge-Offs Impaired Financing Receivable, Related Allowance, Partial Loan Charge-Offs Impaired Financing Receivable, Related Allowance, Partial Loan Charge-Offs Subsequent Events [Abstract] Subsequent Events Subsequent Events [Text Block] 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 [Table] Investment Securities, Description [Axis] Investment Securities, Description [Axis] Investment Securities, Description [Axis] Investment Securities, Description [Domain] Investment Securities, Description [Domain] Investment Securities, Description [Domain] Callable Within One Year Callable Within One Year [Member] Callable Within One Year [Member] Callable Structured Notes Callable Structured Notes [Member] Callable Structured Notes [Member] Schedule of Available for Sale and Held-to-Maturity Securities [Line Items] Schedule of Available for Sale and Held-to-Maturity Securities [Line Items] Schedule of Available for Sale and Held-to-Maturity Securities [Line Items] Available-for-sale Securities, Debt Maturities, Amortized Cost Basis, Rolling Maturity Available-for-sale Securities, Debt Maturities, Amortized Cost Basis, Rolling Maturity [Abstract] Available-for-Sale Amortized Cost, Within One Year Available-for-sale Securities, Debt Maturities, Next Rolling Twelve Months, Amortized Cost Basis Available-for-Sale Amortized Cost, After One Year but Within Five Years Available-for-sale Securities, Debt Maturities, Rolling Year Two Through Five, Amortized Cost Basis Available-for-Sale Amortized Cost, After Five Years but Within Ten Years Available-for-sale Securities, Debt Maturities, Rolling Year Six Through Ten, Amortized Cost Basis Available-for-Sale Amortized Cost, After Ten Years Available-for-sale Securities, Debt Maturities, Rolling after Year Ten, Amortized Cost Basis Available-for-Sale Amortized Cost, Total Available-for-sale Securities, Debt Maturities, Amortized Cost Basis Available-for-sale Securities, Debt Maturities, Fair Value, Rolling Maturity Available-for-sale Securities, Debt Maturities, Fair Value, Rolling Maturity [Abstract] Available-for-Sale Estimated Fair Value, Within One Year Available-for-sale Securities, Debt Maturities, Next Rolling Twelve Months, Fair Value Available-for-Sale Estimated Fair Value, After One Year but Within Five Years Available-for-sale Securities, Debt Maturities, Rolling Year Two Through Five, Fair Value Available-for-Sale Estimated Fair Value, After Ten Years Available-for-sale Securities, Debt Maturities, Rolling Year Six Through Ten, Fair Value Available-for-Sale Estimated Fair Value, After Five Years but Within Ten Years Available-for-sale Securities, Debt Maturities, Rolling after Year Ten, Fair Value Available-for-Sale, Estimated Fair Value Held-to-maturity Securities, Debt Maturities, Net Carrying Amount Held-to-maturity Securities, Debt Maturities, Net Carrying Amount [Abstract] Held-to-Maturity Amortized Cost, Within One Year Held-to-maturity Securities, Debt Maturities, within One Year, Net Carrying Amount Held-to-Maturity Amortized Cost, After One Year but Within Five Years Held-to-maturity Securities, Debt Maturities, after One Through Five Years, Net Carrying Amount Held-to-Maturity Amortized Cost, After Five Years but Within Ten Years Held-to-maturity Securities, Debt Maturities, after Five Through Ten Years, Net Carrying Amount Held-to-Maturity Amortized Cost, After Ten Years Held-to-maturity Securities, Debt Maturities, after Ten Years, Net Carrying Amount Held-to-Maturity Amortized Cost, Total Held-to-maturity Securities, Debt Maturities, Fair Value, Rolling Maturity Held-to-maturity Securities, Debt Maturities, Fair Value, Rolling Maturity [Abstract] Held-to-Maturity Estimated Fair Value, Within One Year Held-to-maturity Securities, Debt Maturities, Next Rolling Twelve Months, Fair Value Held-to-Maturity Estimated Fair Value, After One Year but Within Five Years Held-to-maturity Securities, Debt Maturities, Rolling Year Two Through Five, Fair Value Held-to-Maturity Estimated Fair Value, After Five Years but Within Ten Years Held-to-maturity Securities, Debt Maturities, Rolling Year Six Through Ten, Fair Value Held-to-Maturity Estimated Fair Value, After Ten Years Held-to-maturity Securities, Debt Maturities, Rolling after Ten Years, Fair Value Held-to-Maturity, Estimated Fair Value Available-for-sale Securities and Held-to-maturity Securities Available-for-sale Securities and Held-to-maturity Securities [Abstract] Investment Securities Primarily Classified as Available-for-Sale, Amortized Costs, After One Year but Within Five Years Investment Securities, Primarily Classified as Available-for-Sale, Debt Maturities, Rolling Year Two Through Five, Amortized Cost Basis Investment Securities, Primarily Classified as Available-for-Sale, Debt Maturities, Rolling Year Two Through Five, Amortized Cost Basis Investment Securities Primarily Classified as Available-for-Sale, Fair Value, After One Year but Within Five Years Investment Securities, Primarily Classified as Available-for-Sale, Debt Maturities, Rolling Year Two Through Five, Fair Value Investment Securities, Primarily Classified as Available-for-Sale, Debt Maturities, Rolling Year Two Through Five, Fair Value Schedule of Comprehensive Income (Loss) Schedule of Accumulated Other Comprehensive Income (Loss) Schedule of Accumulated Other Comprehensive Income (Loss) [Table Text Block] Schedule of Financial Assets and Financial Liabilities Measured at Fair Value on a Recurring Basis Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis [Table Text Block] Schedule of Financial Assets and Financial Liabilities Measured at Fair Value on a Non-Recurring Basis Fair Value Measurements, Nonrecurring [Table Text Block] Schedule of Estimated Fair Values of Financial Instruments by Level of Valuation Inputs Fair Value, by Balance Sheet Grouping [Table Text Block] Accounting Changes and Error Corrections [Abstract] Recent Authoritative Accounting Guidance New Accounting Pronouncements and Changes in Accounting Principles [Text Block] Consolidated Statements of Comprehensive Income [Abstract] Consolidated Statements of Comprehensive Income [Abstract] Other comprehensive income (loss), before tax: Other Comprehensive Income (Loss), before Tax [Abstract] Change in net unrealized gains (losses) during period Reclassification adjustment for net gains included in income Defined benefit post-retirement benefits plans: Defined Benefit Pension Plans and Defined Benefit Postretirement Plans Disclosure [Abstract] Change in net actuarial loss Defined Benefit Plan, Actuarial Gain (Loss) Deferred tax benefit (expense) related to other comprehensive income Other comprehensive income (loss), net of tax Comprehensive income, net of tax Comprehensive Income (Loss), Net of Tax, Attributable to Parent Supplemental Disclosures to Consolidated Statement of Cash Flows Cash Flow, Supplemental Disclosures [Text Block] Schedule of Financing Receivable, Troubled Debt Restructurings [Table] Schedule of Financing Receivable, Troubled Debt Restructurings [Table] Residential Construction Real Estate [Member] Residential Construction Real Estate [Member] Residential Construction Real Estate [Member] Financing Receivable, Troubled Debt Restructuring, Concession Type [Axis] Financing Receivable, Troubled Debt Restructuring, Concession Type [Axis] Financing Receivable, Troubled Debt Restructuring, Concession Type [Axis] Financing Receivable, Troubled Debt Restructuring, Concession Type [Domain] Financing Receivable, Troubled Debt Restructuring, Concession Type [Domain] Financing Receivable, Troubled Debt Restructuring, Concession Type [Domain] Interest only period Interest Only Period Concession [Member] Interest Only Period Concession [Member] Extension of terms or maturity Extension of Terms or Maturity Concession [Member] Extension of Terms or Maturity Concession [Member] Interest rate adjustment Interest Rate Adjustment Concession [Member] Interest Rate Adjustment Concession [Member] Other Other Concession [Member] Other Concession [Member] Loans and Leases Receivable, Troubled Debt Restructuring [Line Items] Financing Receivable, Modifications [Line Items] Loans Renegotiated in Troubled Debt Restructurings Financing Receivable, Modifications, Recorded Investment Loans Renegotiated in Troubled Debt Restructurings, Non-Accrual Loans Financing Receivable, Modifications, Recorded Investment, Cash Basis Method Financing Receivable, Modifications, Recorded Investment, Cash Basis Method Loans Renegotiated in Troubled Debt Restructurings, Accrual Loans Financing Receivable, Modifications, Recorded Investment, Accrual Method Financing Receivable, Modifications, Recorded Investment, Accrual Method Number of Notes Financing Receivable, Modifications, Number of Contracts Principle Balance at Restructure Date Financing Receivable, Modifications, Pre-Modification Recorded Investment, Restructured During Period Financing Receivable, Modifications, Pre-Modification Recorded Investment, Restructured During Period Balance Financing Receivable, Modifications, Subsequent Default, Recorded Investment, During Period Financing Receivable, Modifications, Subsequent Default, Recorded Investment, During Period Financing Receivable, Modifications, Subsequent Default, Number of Contracts, During Period Financing Receivable, Modifications, Subsequent Default, Number of Contracts, During Period Financing Receivable, Modifications, Subsequent Default, Number of Contracts, During Period Financing Receivable, Modifications, Subsequent Default, Number of Contracts Financing Receivable, Modifications, Subsequent Default, Number of Contracts State, county and municipal securities US States and Political Subdivisions Debt Securities [Member] Corporate securities Corporate Debt Securities [Member] Other securities Other Debt Obligations [Member] Available-for-Sale Securities, Gross Realized Gains Available-for-sale Securities, Gross Realized Gains Available-for-sale Securities, Gross Realized Losses Available-for-sale Securities, Gross Realized Losses Available-for-Sale: Available-for-sale Securities [Abstract] Available-for-Sale, Amortized Cost Available-for-sale Debt Securities, Amortized Cost Basis Available-for-sale Securities, Gross Unrealized Gain1 Available-for-sale Securities, Gross Unrealized Gain1 Available-for-sale Securities, Gross Unrealized Gain1 Available-for-sale Securities, Gross Unrealized Loss1 Available-for-sale Securities, Gross Unrealized Loss1 Available-for-sale Securities, Gross Unrealized Loss1 Held-to-Maturity: Held-to-maturity Securities, Unclassified [Abstract] Held-to-Maturity, Amortized Cost Held-to-maturity Securities, Gross Unrealized Gain1 Held-to-maturity Securities, Gross Unrealized Gain1 Held-to-maturity Securities, Gross Unrealized Gain1 Held-to-maturity Securities, Gross Unrealized Loss1 Held-to-maturity Securities, Gross Unrealized Loss1 Held-to-maturity Securities, Gross Unrealized Loss1 Financial Instruments with Off-Balance Sheet Risk [Abstract] Financial Instruments with Off Balance Sheet Risk. Entities [Table] Entities [Table] Guarantor Obligations, Nature [Axis] Guarantor Obligations, Nature [Axis] Guarantor Obligations, Nature [Domain] Guarantor Obligations, Nature [Domain] Standby Letters of Credit Financial Standby Letter of Credit [Member] Unused Credit Card Lines Unused Credit Card Lines [Member] Unused Credit Card Lines [Member] Entity Information [Line Items] Entity Information [Line Items] Credit Extension Commitments Credit Extension Commitments Credit Extension Commitments Credit Extension Commitments, Beyond One Year Credit Extension Commitments, Beyond One Year Credit Extension Commitments, Beyond One Year Financial Instruments with Off-Balance Sheet Risk Financial Instruments With Off Balance Sheet Risk [Text Block] Financial Instruments With Off Balance Sheet Risk. Commitments and Contingencies Commitments and Contingencies Disclosure [Text Block] Corporate Debt Securities [Member] Available-for-Sale: Available-for-sale Securities, Continuous Unrealized Loss Position [Abstract] Available-for-sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value Available-for-sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value Available-for-sale Securities, Continuous Unrealized Loss Position, Less Than 12 months, Aggregate Loss1 Available-for-sale Securities, Continuous Unrealized Loss Position, Less Than 12 months, Aggregate Loss1 Available-for-Sale, 12 Months or More Fair Value Available-for-sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value Available-for-sale Securities, Continuous Unrealized Loss Position, 12 months or Longer, Aggregate Loss1 Available-for-sale Securities, Continuous Unrealized Loss Position, 12 months or Longer, Aggregate Loss1 Available-for-sale Securities, Continuous Unrealized Loss Position, 12 months or Longer, Aggregate Loss1 Available-for-Sale, Total Fair Value Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value Available-for-sale Securities, Continuous Unrealized Loss Position, Aggregate Loss1 Available-for-sale Securities, Continuous Unrealized Loss Position, Aggregate Loss1 Available-for-sale Securities, Continuous Unrealized Loss Position, Aggregate Loss1 Held-to-Maturity: Held-to-maturity Securities, Continuous Unrealized Loss Position [Abstract] Held-to-Maturity, Less than 12 Months Fair Value Held-to-maturity Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value Held-to-maturity Securities, Continuous Unrealized Loss Position, Less Than 12 months, Aggregate Loss1 Held-to-maturity Securities, Continuous Unrealized Loss Position, Less Than 12 months, Aggregate Loss1 Held-to-maturity Securities, Continuous Unrealized Loss Position, Less Than 12 months, Aggregate Loss1 Held-to-Maturity, 12 Months or More Fair Value Held-to-maturity Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value Held-to-Maturity, 12 Months or More Gross Unrealized Losses Held-to-maturity Securities, Continuous Unrealized Loss Position, 12 months or Longer, Aggregate Loss1 Held-to-maturity Securities, Continuous Unrealized Loss Position, 12 months or Longer, Aggregate Loss1 Held-to-Maturity, Total Fair Value Held-to-maturity Securities, Continuous Unrealized Loss Position, Fair Value Held-to-maturity Securities, Continuous Unrealized Loss Position, Aggregate Loss1 Held-to-maturity Securities, Continuous Unrealized Loss Position, Aggregate Loss1 Held-to-maturity Securities, Continuous Unrealized Loss Position, Aggregate Loss1 Available-for-Sale and Held-to-Maturity: Available-for-Sale and Held-to-Maturity, Securities in Unrealized Loss Positions [Abstract] Available-for-Sale and Held-to-Maturity, Securities in Unrealized Loss Positions [Abstract] Investment Securities in an Unrealized Loss Position (Number of Securities) Available-for-Sale and Held-to-Maturity, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions Available-for-Sale and Held-to-Maturity, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions Gross realized gains Gross realized losses Real Estate Acquired Through Foreclosure [Roll Forward] Real Estate Acquired Through Foreclosure [Roll Forward] Real Estate Acquired Through Foreclosure [Roll Forward] Beginning balance Additions Real Estate Acquired Through Foreclosure, Additions Real Estate Acquired Through Foreclosure, Additions Capitalized improvements Real Estate Acquired Through Foreclosure, Improvements Real Estate Acquired Through Foreclosure, Improvements Valuation adjustments Real Estate Acquired Through Foreclosure, Valuation Adjustments Real Estate Acquired Through Foreclosure, Valuation Adjustments Dispositions Real Estate Acquired Through Foreclosure, Disposals Real Estate Acquired Through Foreclosure, Disposals Ending balance Schedule of Impaired Financing Receivable [Table] Schedule of Impaired Financing Receivable [Table] Loans and Leases Receivable Recorded Investment, Impaired [Line Items] Financing Receivable, Impaired [Line Items] Impaired Financing Receivable, Unpaid Principal Balance Impaired Financing Receivable, Unpaid Principal Balance [Abstract] Unpaid Total Principal Balance Impaired Financing Receivable, Unpaid Principal Balance Recorded Investment With No Allowance Impaired Financing Receivable, with No Related Allowance, Recorded Investment Recorded Investment With Allowance Impaired Financing Receivable, with Related Allowance, Recorded Investment Total Recorded Investment Impaired Financing Receivable, Recorded Investment Impaired Financing Receivable, Average Recorded Investment and Cash Basis Method Interest Income Impaired Financing Receivable, Average Recorded Investment and Cash Basis Method Interest Income [Abstract] Impaired Financing Receivable, Average Recorded Investment and Cash Basis Method Interest Income [Abstract] Average Recorded Investment Impaired Financing Receivable, Average Recorded Investment Income Recognized Impaired Financing Receivable, Interest Income, Accrual Method and Cash Basis Method Impaired Financing Receivable, Interest Income, Accrual Method and Cash Basis Method Interest Income on Impaired Loans If Interest Had Been Accrued Impaired Financing Receivable, Interest Income, Accrual Method Schedule of Loans by Class Schedule of Accounts, Notes, Loans and Financing Receivable [Table Text Block] Schedule of Recorded Investment in Past Due Loans by Class Past Due Financing Receivables [Table Text Block] Schedule of Recorded Investment in Impaired Loans Impaired Financing Receivables [Table Text Block] Schedule of Loans Renegotiated in Troubled Debt Restructurings Troubled Debt Restructurings on Financing Receivables [Table Text Block] Schedule of Recorded Investment in Criticized Loans by Class and Credit Quality Indicator Financing Receivable Credit Quality Indicators [Table Text Block] Fair Value, by Balance Sheet Grouping [Table] Fair Value, by Balance Sheet Grouping [Table] Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] Financial assets: Financial Instruments, Financial Assets, Balance Sheet Groupings [Abstract] Cash and cash equivalents Cash and Cash Equivalents, Fair Value Disclosure Investment securities held-to-maturity Accrued interest receivable Accrued Interest Receivable, Fair Value Disclosure Accrued Interest Receivable, Fair Value Disclosure Net loans Loans Receivable, Fair Value Disclosure Total financial assets Assets, Fair Value Disclosure Financial liabilities: Financial Instruments, Financial Liabilities, Balance Sheet Groupings [Abstract] Total deposits, excluding time deposits Deposits, Excluding Time Deposits, Fair Value Disclosure Deposits, Excluding Time Deposits, Fair Value Disclosure Time deposits Time Deposits, Fair Value Disclosure Time Deposits, Fair Value Disclosure Securities sold under repurchase agreements Financial Instruments Sold, Not yet Purchased, at Fair Value Other borrowed funds Other Borrowed Funds, Fair Value Disclosure Other Borrowed Funds, Fair Value Disclosure Accrued interest payable Accrued Interest Payable, Fair Value Disclosure Accrued Interest Payable, Fair Value Disclosure Long-term debt Other Long Term Debt, Fair Value Disclosure Other Long Term Debt, Fair Value Disclosure Preferred Stock, Pending Redemption Subordinated debentures held by subsidiary trusts Subordinated Debt Obligations, Fair Value Disclosure Total financial liabilities Financial and Nonfinancial Liabilities, Fair Value Disclosure Common stock Common shares purchased and retired Stock Repurchased and Retired During Period, Shares Common shares issued Stock Issued During Period, Shares, New Issues Non-vested common shares issued Stock Issued During Period, Shares, Restricted Stock Award, Gross Non-vested common shares forfeited Stock Issued During Period, Shares, Restricted Stock Award, Forfeited Stock options exercised Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period Shares tendered in payment of option price and income tax withholding amounts Shares tendered in payment of option price and income tax withholding amounts, shares Shares tendered in payment of option price and income tax with holding amounts. Common (in dollars per share) Common Stock, Dividends, Per Share, Declared Preferred (in dollars per share) Preferred Stock, Dividend Rate, Percentage Schedule of Compliance with Regulatory Capital Requirements under Banking Regulations [Table] Schedule of Compliance with Regulatory Capital Requirements under Banking Regulations [Table] Legal Entity [Axis] Legal Entity [Axis] Entity [Domain] Entity [Domain] FIB First Interstate Bank [Member] First Interstate Bank [Member] Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items] Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items] Total risk-based capital: Capital [Abstract] Actual Amount Capital Actual Ratio Capital to Risk Weighted Assets Adequately Capitalized Amount Capital Required for Capital Adequacy Adequately Capitalized Ratio Capital Required for Capital Adequacy to Risk Weighted Assets Well Capitalized Amount Capital Required to be Well Capitalized Well Capitalized Ratio Capital Required to be Well Capitalized to Risk Weighted Assets Tier 1 risk-based capital: Tier One Risk Based Capital [Abstract] Actual Amount Tier One Risk Based Capital Actual Ratio Tier One Risk Based Capital to Risk Weighted Assets Adequately Capitalized Amount Tier One Risk Based Capital Required for Capital Adequacy Adequately Capitalized Ratio Tier One Risk Based Capital Required for Capital Adequacy to Risk Weighted Assets Well Capitalized Amount Tier One Risk Based Capital Required to be Well Capitalized Well Capitalized Ratio Tier One Risk Based Capital Required to be Well Capitalized to Risk Weighted Assets Leverage capital ratio: Tier One Leverage Capital [Abstract] Actual Ratio Tier One Leverage Capital to Average Assets Adequately Capitalized Amount Tier One Leverage Capital Required for Capital Adequacy Adequately Capitalized Ratio Tier One Leverage Capital Required for Capital Adequacy to Average Assets Well Capitalized Amount Tier One Leverage Capital Required to be Well Capitalized Well Capitalized Ratio Tier One Leverage Capital Required to be Well Capitalized to Average Assets Earnings per Common Share Earnings Per Share [Text Block]