Amendment Flag Current Fiscal Year End Date Document Period End Date Entity [Domain] Entity Well-known Seasoned Issuer Entity Voluntary Filers Entity Current Reporting Status Entity Filer Category Entity Public Float Entity Registrant Name Entity Central Index Key Entity Common Stock, Shares Outstanding Document Fiscal Year Focus Document Fiscal Period Focus Legal Entity [Axis] Document Type Awards Type [Axis] Award Type [Axis] Accounting Policies [Abstract] Accrued interest payable Accounts, Notes, Loans and Financing Receivable [Line Items] Amortization of securities premiums and discounts, net Accretion (Amortization) of Discounts and Premiums, Investments Accumulated other comprehensive loss, net of tax Accumulated Other Comprehensive Income [Abstract] Other comprehensive loss [Abstract] Unrealized Gains (Losses) on AFS Securities [Member] Accumulated Net Investment Gain (Loss) Attributable to Parent [Member] Less accumulated depreciation and amortization Accumulated Depreciation, Depletion and Amortization, Property, Plant, and Equipment Accumulated Other Comprehensive Income (Loss), Net of Tax [Member] AOCI Attributable to Parent [Member] Capital surplus Capital Surplus [Member] Adjustments to reconcile net income to net cash provided by operating activities [Abstract] Adjustments to reconcile net income to net cash provided by operating activities: Adjustments for New Accounting Pronouncements [Axis] Stock-based compensation Adjustments to Additional Paid in Capital, Share-based Compensation, Requisite Service Period Recognition Advances from Federal Home Loan Bank Total FHLB advances Advances from Federal Home Loan Banks Advances from Federal Home Loan Bank [Abstract] Losses charged off Allowance for Loan and Lease Losses, Write-offs Recoveries Activity in Allowance for Loan and Lease Losses Allowance for loan losses [Roll Forward] Allowance for Loan and Lease Losses [Roll Forward] Allowance for Loan and Lease Losses Allowance for Credit Losses [Text Block] Amortization Amortization of Intangible Assets Ancillary fees Antidilutive Securities [Axis] Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items] Antidilutive Securities, Name [Domain] Options excluded from diluted calculations (in shares) Fair value Assets: Assets [Abstract] Total assets Assets Repurchase Agreements and Similar Transactions, Maturity Periods [Axis] Repurchase Agreements and Similar Transactions, Maturity Periods [Domain] Less than 12 months Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss 12 months or more Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss Unrealized holding loss on securities Available-for-sale Securities, Accumulated Gross Unrealized Gain (Loss), before Tax Total Available-for-sale Securities, Continuous Unrealized Loss Position, Accumulated Loss Amortized cost Equity securities Available-for-sale, fair value [Abstract] Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value [Abstract] Available-for-sale Debt Securities [Abstract] Available-for-sale Equity Securities [Abstract] Gross unrealized gains Available-for-sale Securities, Accumulated Gross Unrealized Gain, before Tax Due after five through ten years Available-for-sale Securities, Debt Maturities, Year Six Through Ten, Amortized Cost Basis Gross unrealized losses Available-for-sale Equity Securities, Accumulated Gross Unrealized Loss, before Tax 12 months or more Available-for-sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value Total Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value Carrying value of investment securities available for sale pledged as collateral under repurchase agreements Available-for-sale Securities Pledged as Collateral Securities Available-for-Sale [Abstract] Available-for-sale Securities, Fair Value to Amortized Cost Basis [Abstract] Securities available-for-sale at fair value (amortized cost of $590,199 and $608,939, respectively) Available-for-sale securities Total securities Securities available-for-sale Gross unrealized losses Available-for-sale Securities, Accumulated Gross Unrealized Loss, before Tax Less than 12 months Available-for-sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value Gross unrealized gains Available-for-sale Equity Securities, Accumulated Gross Unrealized Gain, before Tax Due after five through ten years Available-for-sale Securities, Debt Maturities, Year Six Through Ten, Fair Value Available-for-sale, gross unrealized losses [Abstract] Available-for-sale Securities, Continuous Unrealized Loss Position, Aggregate Loss [Abstract] Gross unrealized gains Available-for-sale Debt Securities, Accumulated Gross Unrealized Gain, before Tax Gross unrealized losses Available-for-sale Debt Securities, Accumulated Gross Unrealized Loss, before Tax Securities available-for-sale at amortized cost Amortized cost Available-for-sale Securities, Amortized Cost Basis Available-for-Sale, continuous unrealized loss position [Abstract] Available-for-sale Securities, Continuous Unrealized Loss Position [Abstract] Securities available-for-sale (AFS): Amortized cost Available-for-sale Debt Securities, Amortized Cost Basis Fair value Total debt securities Available-for-sale Securities, Debt Securities Available-for-sale, amortized cost [Abstract] Available-for-sale Securities, Debt Maturities, Amortized Cost Basis, Fiscal Year Maturity [Abstract] Due after ten years Available-for-sale Securities, Debt Maturities, after Ten Years, Fair Value Due after ten years Available-for-sale Securities, Debt Maturities, after Ten Years, Amortized Cost Basis Due after one through five years Available-for-sale Securities, Debt Maturities, Year Two Through Five, Amortized Cost Basis Pre-tax loss on sale of securities Due after one through five years Available-for-sale Securities, Debt Maturities, Year Two Through Five, Fair Value Securities (gains) losses Securities gains (losses) Net gain (loss) realized on sales and calls of AFS securities Without single maturity date Available-for-sale Securities, Debt Maturities, without Single Maturity Date, Amortized Cost Basis Realized pre-tax gain on sale of securities Fair value Available-for-sale Securities, Equity Securities Available-for-sale, fair value [Abstract] Available-for-sale Securities, Debt Maturities, Fair Value, Fiscal Year Maturity [Abstract] Without single maturity date Available-for-sale Securities, Debt Maturities, without Single Maturity Date, Fair Value Due in one year or less Available-for-sale Securities, Debt Maturities, Next Twelve Months, Amortized Cost Basis Due in one year or less Available-for-sale Securities, Debt Maturities, Next Twelve Months, Fair Value Bank owned life insurance Bank owned life insurance Bank Owned Life Insurance Income Mortgage Banking and Servicing Rights Banking and Thrift Disclosure [Text Block] Basis of Presentation Brokerage revenue Buildings [Member] Counterparty Name [Axis] Total capital (to risk weighted assets), Amount [Abstract] Actual Amount Capital Net present value of all potential lease payments Capital Leases, Future Minimum Payments, Present Value of Net Minimum Payments For Capital Adequacy Purposes Capital Required for Capital Adequacy to Risk Weighted Assets To Be Well-Capitalized Under Prompt Corrective Action Provision Capital Required to be Well Capitalized For Capital Adequacy Purposes Capital Required for Capital Adequacy Actual Ratio Capital to Risk Weighted Assets To Be Well-Capitalized Under Prompt Corrective Action Provision Capital Required to be Well Capitalized to Risk Weighted Assets Carrying Amount [Member] Cash and Due from Banks and Interest Bearing Deposits Cash and Cash Equivalents Disclosure [Text Block] Cash and Cash Equivalents [Line Items] Cash and due from banks Cash on deposit Cash and Cash Equivalents Cash and cash equivalents at end of year Cash and cash equivalents Cash and cash equivalents at beginning of year Cash and Cash Equivalents, at Carrying Value Net increase (decrease) in cash and cash equivalents Cash and Cash Equivalents, Period Increase (Decrease) Balance requirements Cash and Securities Segregated under Federal and Other Regulations Cash and cash equivalents Cash and Cash Equivalents, Fair Value Disclosure Cash and Due from Banks and Interest Bearing Deposits [Abstract] Cash accounts which exceeded federally insured limits Certificates of deposit in other banks Certificates of Deposit, at Carrying Value Commercial [Member] Commercial [Member] Commercial Portfolio Segment [Member] Commercial [Member] Commercial Real Estate Portfolio Segment [Member] Commitments and Contingencies Commitments and Contingencies Disclosure [Text Block] Commitments and contingencies (notes 18 and 20) Commitments and Contingencies Commitments to Extend Credit [Member] Commitments and Contingencies [Abstract] Cash dividends declared (in dollars per share) Dividends declared per share (in dollars per share) Common Stock [Member] Common stock, shares authorized (in shares) Common equity Tier 1 capital (to risk weighted assets), Amount [Abstract] Common Equity Tier One Capital [Abstract] Actual Amount Common Equity Tier One Capital Actual Ratio Common Equity Tier One Capital Ratio For Capital Adequacy Purposes Common Equity Tier One Capital Required for Capital Adequacy To Be Well-Capitalized Under Prompt Corrective Action Provision Common Equity Tier One Capital Required to be Well-Capitalized Common stock, par value (in dollars per share) Common stock, $5 par value, shares authorized 25,000,000; shares outstanding 2017 - 17,692,912; 2016 - 17,628,695 Common Stock, Value, Outstanding Balance (in shares) Balance (in shares) Common stock, shares outstanding (in shares) Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items] Deferred tax assets [Abstract] Components of the net deferred tax liability [Abstract] Deferred tax liabilities [Abstract] Comprehensive Income Comprehensive income Comprehensive Income (Loss), Net of Tax, Attributable to Parent Concentration Risk Type [Domain] Concentrations of Credit Risk Concentration Risk Disclosure [Text Block] Concentration Risk [Line Items] Concentration Risk Type [Axis] Concentration Risk [Table] Concentration of credit risk Condensed Financial Statements, Captions [Line Items] Parent Company Financial Statements Condensed Financial Information of Parent Company Only Disclosure [Text Block] Parent Company Financial Statements [Abstract] Consolidated Entities [Domain] Consolidated Entities [Axis] Construction [Member] Construction Loans [Member] Construction in Progress [Member] Consumer [Member] Consumer Portfolio Segment [Member] Rate Modification [Member] Contractual Interest Rate Reduction [Member] Servicing fees Contractually Specified Servicing Fees, Amount Core Deposit Intangible [Member] Core Deposits [Member] Credit Facility [Domain] Credit Facility [Axis] Implementation of ASU 2018-02 Cumulative Effect on Retained Earnings, Net of Tax Current income tax expense Doubtful [Member] Description of variable rate basis Debt Instrument [Axis] Debt Security [Axis] Debt instrument, repurchased face amount Basis spread on variable rate Borrowings Debt Disclosure [Text Block] Average interest rate Maturity period of debentures Debt Instrument, Term Borrowings [Abstract] Maturity date of junior subordinated debentures Maturity date of line of credit Interest rate on junior subordinated debentures Schedule of Long-term Debt Instruments [Table] Debt Instrument [Line Items] Debt Instrument, Name [Domain] Debt Securities [Member] Debt Securities [Member] Unrealized losses on AFS securities Deferred Tax Assets, Unrealized Losses on Available-for-Sale Securities, Gross Limited partnership investments Deferred Tax Assets, Investments Limited partnership investments Deferred Tax Liabilities, Investments Deferred taxes Deferred Income Tax Liabilities, Net Deferred taxes Total deferred tax liabilities Deferred Tax Liabilities, Gross Other Total deferred tax assets Deferred Tax Assets, Gross Accrued expenses Allowance for loan and lease losses Deferred Tax Assets, Tax Deferred Expense, Reserves and Accruals, Provision for Loan Losses Depreciation and amortization Deferred Tax Liabilities, Property, Plant and Equipment Mortgage servicing rights Deferred Tax Liabilities, Mortgage Servicing Rights Net deferred tax liability Deferred Tax Liabilities, Net Other Deferred Tax Liabilities, Other Defined Contribution Plan Disclosure [Line Items] Defined Contribution Plan, Type [Extensible List] Percentage of employee contribution, maximum Defined Contribution Plan, Maximum Annual Contributions Per Employee, Percent Defined Contribution Plan [Table] Maximum contribution on employees gross pay Employer matching contribution Contribution by employer under 401(K) plan Major Classifications of Deposits Deposit Liabilities, Type [Table Text Block] Deposits Deposit Liabilities Disclosures [Text Block] Deposits [Abstract] Deposits: Money market deposits Total deposits Deposits NOW accounts Deposits Deposits, Fair Value Disclosure Savings Depreciation and amortization of premises and equipment Depreciation Depreciation and amortization Depreciation expense Director Who is Shareholder in Law Firm [Member] Director [Member] Repurchase Agreements [Abstract] Employee Benefits [Abstract] Employee Benefits Disclosure of Compensation Related Costs, Share-based Payments [Text Block] Cash dividends declared Dividends, Common Stock, Cash Dividends paid on restricted stock shares Basic earnings per share [Abstract] Earnings Per Share, Basic [Abstract] Diluted earnings per share (in dollars per share) Earnings Per Share Diluted earnings per share [Abstract] Earnings Per Share, Diluted [Abstract] Earnings per share [Abstract] Earnings Per Share, Basic and Diluted [Abstract] Basic earnings per share (in dollars per share) Earnings Per Share ("EPS") Earnings Per Share [Abstract] Bank owned life insurance Effective Income Tax Rate Reconciliation, Nondeductible Expense, Life Insurance, Percent Federal corporate tax rate Computed at the statutory rate Housing and new markets credits Effective Income Tax Rate Reconciliation, Tax Credit, Investment, Percent ESOP dividend deduction Effective Income Tax Rate Reconciliation, Deduction, Employee Stock Ownership Plan Dividend, Percent Dividends received deduction Effective Income Tax Rate Reconciliation, Deduction, Dividend, Percent Other, net Effective Income Tax Rate Reconciliation, Other Adjustments, Percent Tax-exempt interest Effective Income Tax Rate Reconciliation, Tax Exempt Income, Percent Reconciliation of income tax expense at the statutory rate to actual income tax expense [Abstract] Total Effective Income Tax Rate Reconciliation, Percent Employee Stock Ownership Plan (ESOP) Disclosures [Line Items] Employee Stock Ownership Plan (ESOP) Name [Axis] Tax benefit realized for the tax deductions from option exercises of the share-based payment arrangements for the year Options [Member] Stock Options [Member] Contributions to ESOP by employer Unrecognized compensation cost of unvested share-based compensation arrangements granted under the plan at year-end Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized Expected period for recognition of unrecognized compensation cost Employee Stock Ownership Plan (ESOP), Plan [Domain] Number of allocated shares under ESOP (in shares) Equipment Equity Component [Domain] Marketable Equity Securities [Member] Fair Value [Member] Estimate of Fair Value Measurement [Member] Excess tax benefits of stock-based compensation Excess Tax Benefit from Share-based Compensation, Financing Activities Excess tax benefits of stock-based compensation Excess Tax Benefit from Share-based Compensation, Operating Activities Term Modification [Member] Extended Maturity [Member] Comparability adjustments Fair Value Inputs, Comparability Adjustments Constant prepayment rate Fair Value Inputs, Prepayment Rate Unobservable inputs [Abstract] Marketability discount Fair Value Inputs, Discount for Lack of Marketability Total recognized gains (losses) Included in net income Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Earnings Probability of default Fair Value Inputs, Probability of Default Fair Value Inputs, Assets, Quantitative Information [Line Items] Total gains (losses) for the period included in net income attributable to the change in unrealized gains or losses related to assets still held at the reporting date Fair Value, Assets Measured on Recurring Basis, Change in Unrealized Gain (Loss) Fair Value Inputs, Assets, Quantitative Information [Table] Quantitative Information about Unobservable Inputs Used in Recurring and Nonrecurring Level 3 Fair Value Measurements Discount rate Total off-balance sheet financial instruments Transfers between Fair Value Hierarchy Levels Fair Value Transfer, Policy [Policy Text Block] Settlements Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Settlements Measurement Basis [Axis] Fair Value, Hierarchy [Axis] Measurement Frequency [Axis] Nonrecurring [Member] Asset Class [Axis] Fair Value Measurements, Recurring and Nonrecurring [Table] Issues Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] Fair Value, Measurement Frequency [Domain] Fair Market Value of Financial Assets and Liabilities [Abstract] Asset Class [Domain] Recurring [Member] Fair Value Hierarchy [Domain] Fair Market Value of Financial Assets and Liabilities Realized and Unrealized Gains and Losses for Items Included in Net Income in the Consolidated Statements of Income Fair Value Measurements of Recognized Assets Measured on Nonrecurring Basis Reconciliation of the Beginning and Ending Balance of Recurring Fair Value Measurements Using Significant Unobservable (Level 3) Inputs Fair Value, by Balance Sheet Grouping [Table] Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Table] Fair Value of Financial Instruments and Levels within the Fair Value Hierarchy of the Valuation Techniques Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] Reconciliation of beginning and ending balances of recurring fair value measurements recognized in balance sheet using significant unobservable (Level 3) inputs [Roll Forward] Fair Value Assets Measured on Recurring Basis Fair Value, Assets Measured on Recurring Basis [Table Text Block] Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] Fair Value Measurement [Domain] Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] Fair Value, Inputs, Level 1 [Member] Significant Other Observable Inputs (Level 2) [Member] Fair Value, Inputs, Level 2 [Member] Significant Unobservable Inputs (Level 3) [Member] Fair Value, Inputs, Level 3 [Member] Ending balance Beginning balance Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items] Federal Home Loan Bank, Advances [Line Items] FDIC insurance Federal funds purchased Federal funds purchased Federal home loan bank stock used as collateral for advances Federal Home Loan Bank, Advances, General Debt Obligations, Disclosures, Collateral Pledged Federal funds purchased Federal Funds Purchased and Securities Loaned or Sold under Agreements to Repurchase, Fair Value Disclosure Federal Funds Purchased [Member] Federal Home Loan Bank, Advances [Table] Advances from Federal Home Loan Bank Federal Home Loan Bank Borrowings, Fair Value Disclosure Federal funds sold Federal Home Loan Bank stock Advances from Federal Home Loan Bank Federal Home Loan Bank Advances, Disclosure [Text Block] Federal home loan bank advances, interest rate Federal Home Loan Bank, Advances, Branch of FHLB Bank, Interest Rate Federal Home Loan Bank Advances [Member] Federal home loan bank advances available After 5 Years Federal Home Loan Bank, Advances, Maturities Summary, Due after Year Five 2 Years Federal Home Loan Bank, Advances, Maturities Summary, Due in Year Two 3 Years Federal Home Loan Bank, Advances, Maturities Summary, Due in Year Three 5 Years Federal Home Loan Bank, Advances, Maturities Summary, Due in Year Five FHLB maximum borrowing capacity Federal Home Loan Bank, Advances, General Debt Obligations, Maximum Amount Available 4 Years Federal Home Loan Bank, Advances, Maturities Summary, Due in Year Four Federal Reserve Bank stock Within 1 Year Federal Home Loan Bank, Advances, Maturities Summary, Due in Next Twelve Months Mortgage banking income Fees and Commissions, Mortgage Banking Trust and wealth management income Service charges on deposit accounts Loans Held for Sale Loans Finance, Loan and Lease Receivables, Held-for-investment, Policy [Policy Text Block] Financial Instrument [Axis] Financial Instrument Performance Status [Axis] Financial Instrument Performance Status [Domain] Financial liabilities [Abstract] Financial assets [Abstract] Financial Instruments, Financial Assets, Balance Sheet Groupings [Abstract] Financing Receivable, Recorded Investment, Past Due [Line Items] Post-Modification Outstanding Balance Financing Receivable, Modifications, Post-Modification Recorded Investment Bank's Loan portfolio aging analysis, segregated by class [Abstract] Financing Receivable, Modifications [Line Items] Defaulted restructured loans, number of loans Financing Receivable, Modifications, Subsequent Default, Number of Contracts Collectively evaluated for impairment Financing Receivable, Collectively Evaluated for Impairment Individually evaluated for impairment Financing Receivable, Allowance for Credit Losses, Individually Evaluated for Impairment Financing Receivable, Allowance for Credit Losses [Line Items] Class of Financing Receivable, Type [Domain] Class of Financing Receivable, Type [Domain] Financing Receivable, Recorded Investment [Line Items] 90+ and Accruing 90+ Days Past Due [Member] Financing Receivables, Equal to Greater than 90 Days Past Due [Member] Individually evaluated for impairment Financing Receivable, Individually Evaluated for Impairment 60-89 Days Past Due [Member] Financing Receivables, 60 to 89 Days Past Due [Member] Financing Receivable Portfolio Segment [Domain] Financing Receivable Portfolio Segment [Axis] Credit Risk Profile of the Bank's Commercial Loan Portfolio Based on Rating Category and Payment Activity, Segregated by Class of Loans Financing Receivable Credit Quality Indicators [Table Text Block] Collectively evaluated for impairment Financing Receivable, Allowance for Credit Losses, Collectively Evaluated for Impairment Defaulted restructured loans, recorded balance Financing Receivable, Modifications, Subsequent Default, Recorded Investment 30-59 Days Past Due [Member] Financing Receivables, 30 to 59 Days Past Due [Member] Allowance for loan losses ending balance [Abstract] Financing Receivable, Allowance for Credit Loss, Additional Information [Abstract] Financing Receivable, Impaired [Line Items] Financing Receivables, Period Past Due [Domain] Financing Receivables, Period Past Due [Axis] Number of Loans Current Class of Financing Receivable, Type [Axis] Class of Financing Receivable, Type [Axis] Class of Financing Receivable, Type [Axis] Total Past Due Financing Receivable, Recorded Investment, Past Due Nonaccrual loans segregated by class of loans Financing Receivable, Recorded Investment, Nonaccrual Status Beginning balance, January 1 Ending balance, December 31 Core deposit intangible (net of accumulated amortization of $8,616 and $8,483, respectively) Finite-Lived Intangible Assets [Line Items] Core deposit intangible, accumulated amortization Finite-Lived Intangible Assets, Accumulated Amortization Finite-Lived Intangible Assets by Major Class [Axis] Finite-lived Intangible Assets [Roll Forward] Finite-Lived Intangible Assets, Major Class Name [Domain] Repossession expense Foreclosed Real Estate Expense Furniture, Fixtures, and Equipment [Member] Furniture and Fixtures [Member] Gain on repurchase of debt instrument Gain on debt repurchase Gain (Loss) on Repurchase of Debt Instrument Net gain on sale of mortgage loans held for sale Gain (Loss) on Sale of Mortgage Loans Gains (losses) on sale of assets, net Gain (Loss) on Disposition of Property Plant Equipment Gains on sale of loans held for sale Gains on sales of loans, net Goodwill Goodwill and Core Deposit Intangible Goodwill and Core Deposit Intangible [Abstract] Gross unrealized gains Held-to-maturity Securities, Accumulated Unrecognized Holding Gain Due after ten years Held-to-maturity Securities, Debt Maturities, after Ten Years, Net Carrying Amount Summary of Amortized Cost and Fair Value of Held-to-maturity Securities Held-to-maturity Securities [Table Text Block] Due after five through ten years Held-to-maturity Securities, Debt Maturities, after Five Through Ten Years, Net Carrying Amount Gross unrealized losses Held-to-maturity Securities, Accumulated Unrecognized Holding Loss Due after one through five years Held-to-maturity Securities, Debt Maturities, after One Through Five Years, Net Carrying Amount Securities held-to-maturity at amortized cost (fair value of $660 and $867, respectively) Amortized cost Securities held-to-maturity (HTM): Securities Held-to-Maturity [Abstract] Due after ten years Held-to-maturity Securities, Debt Maturities, after Ten Years, Fair Value Due after one through five years Held-to-maturity Securities, Debt Maturities, Year Two Through Five, Fair Value Due after five through ten years Held-to-maturity Securities, Debt Maturities, Year Six Through Ten, Fair Value Held-to-maturity, amortized cost [Abstract] Held-to-maturity Securities, Debt Maturities, Net Carrying Amount [Abstract] Due in one year or less Held-to-maturity Securities, Debt Maturities, within One Year, Net Carrying Amount Securities held-to-maturity at fair value Fair value Total debt securities Securities held-to-maturity Held-to-maturity, fair value [Abstract] Held-to-maturity Securities, Debt Maturities, Fair Value, Fiscal Year Maturity [Abstract] Without single maturity date Held-to-maturity Securities, Debt Maturities, without Single Maturity Date, Net Carrying Amount Due in one year or less Held-to-maturity Securities, Debt Maturities, Next Twelve Months, Fair Value Without single maturity date Held-to-maturity Securities, Debt Maturities, without Single Maturity Date, Fair Value Home Equity [Member] Home Equity Line of Credit [Member] Interest Income Recognized Impaired Financing Receivable, with No Related Allowance, Interest Income, Accrual Method Interest Income Recognized Recorded Balance Impaired Financing Receivable, with No Related Allowance, Recorded Investment Specific Allowance Specific Allowance Impaired Financing Receivable, Related Allowance Average Investment in Impaired Loans Impaired Financing Receivable, with No Related Allowance, Average Recorded Investment Interest Income Recognized Impaired Financing Receivable, with Related Allowance, Interest Income, Accrual Method Unpaid Contractual Principal Balance Impaired Financing Receivable, with No Related Allowance, Unpaid Principal Balance Impaired Loans, Average Investment in Impaired Loans, and Interest Income Recognized on Impaired Loans Recorded Balance Recorded Balance Impaired Financing Receivable, with Related Allowance, Recorded Investment Average Investment in Impaired Loans Impaired Financing Receivable, Average Recorded Investment Unpaid Contractual Principal Balance Impaired Financing Receivable, with Related Allowance, Unpaid Principal Balance Unpaid Contractual Principal Balance Average Investment in Impaired Loans Impaired Financing Receivable, with Related Allowance, Average Recorded Investment Income Taxes [Abstract] Equity in undistributed earnings of subsidiaries Equity in undistributed income of subsidiaries Income (Loss) from Subsidiaries, Net of Tax Discount Cash Flows, Computer Pricing Model [Member] Income before income taxes Income before income taxes and equity in undistributed income of subsidiaries Income (Loss) from Continuing Operations before Equity Method Investments, Income Taxes, Noncontrolling Interest Consolidated Statements of Income and Comprehensive Income [Abstract] Condensed Statements of Income and Comprehensive Income [Abstract] Income Taxes Income Tax Disclosure [Text Block] Computed at the statutory rate Effective Income Tax Rate Reconciliation at Federal Statutory Income Tax Rate, Amount Components of the provision for income taxes [Abstract] Reconciliation of income tax expense at the statutory rate to actual income tax expense [Abstract] Effective Income Tax Rate Reconciliation, Amount [Abstract] ESOP dividend deduction Effective Income Tax Rate Reconciliation, Deduction, Employee Stock Ownership Plan Dividend, Amount Income taxes Total income tax expense Tax expense (benefit) Income tax benefit Dividends received deduction Effective Income Tax Rate Reconciliation, Deduction, Dividends, Amount Stock option exercises and restricted stock vesting Effective Income Tax Rate Reconciliation, Nondeductible Expense, Share-based Compensation Cost, Amount Other, net Effective Income Tax Rate Reconciliation, Other Adjustments, Amount Income taxes paid Income Taxes Tax-exempt interest Effective Income Tax Rate Reconciliation, Tax Exempt Income, Amount Housing and new markets credits Effective Income Tax Rate Reconciliation, Tax Credit, Other, Amount Change in repurchase agreements and federal funds purchased, net Change in deposits, net Changes in [Abstract] Changes in: Other assets Increase (Decrease) in Other Operating Assets Change in cash surrender value of bank owned life insurance Other liabilities Increase (Decrease) in Other Operating Liabilities Increase (Decrease) in Stockholders' Equity [Roll forward] Dilutive effect of equity grants (in shares) Data processing Interest and dividends on securities: Interest and fees on loans, including loans held for sale Total interest income Interest and Dividend Income, Operating Interest expense: Interest on deposits Interest on advances from Federal Home Loan Bank Interest on long-term debt Total interest expense Interest expense Interest on repurchase agreements Interest Expense, Securities Sold under Agreements to Repurchase Net interest income after provision for loan losses Interest Income (Expense), after Provision for Loan Loss Net interest income Interest Income (Expense), Net Interest income: Tax exempt Other, including interest on federal funds sold Interest Income, Federal Funds Sold Taxable Interest paid Interest bearing Interest bearing deposits Internal Credit Assessment [Axis] Internal Credit Assessment [Domain] Dividends from subsidiary banks Investment Income, Dividend Federal Home Loan Bank stock Investment in Federal Home Loan Bank Stock, Fair Value Disclosure Quarterly increase in amortization expense Investment Income, Amortization of Premium Securities Investment in and advances to subsidiaries Investments in and Advance to Affiliates, Subsidiaries, Associates, and Joint Ventures Amortized Cost and Fair Value of Securities by Contractual Maturity Investments Classified by Contractual Maturity Date [Table Text Block] Securities [Abstract] Junior Subordinated Debentures [Member] Long-term debt Long-term debt Junior Subordinated Debenture Owed to Unconsolidated Subsidiary Trust LIBOR Rate [Member] London Interbank Offered Rate (LIBOR) [Member] Long-term Debt, Type [Domain] Long-term Debt, Type [Axis] Land and Buildings [Member] Land and Building [Member] Late fees Leasehold Improvements [Member] Operating Leases Leases of Lessee Disclosure [Text Block] Operating Leases [Abstract] Legal fees Tier I capital (to average assets), Ratio [Abstract] Total liabilities and shareholders' equity Liabilities and Equity Total liabilities Liabilities Liabilities and shareholders' equity: Liabilities and shareholders' equity [Abstract] Credit loss reserve Liability for Claims and Claims Adjustment Expense Line of Credit Facility [Table] Line of Credit Facility [Line Items] Unused commitment fee Maximum borrowing capacity under line of credit Remaining borrowing capacity available for general corporate purposes Loan Restructuring Modification [Domain] Loan Restructuring Modification [Axis] Repayments Loans and Leases Receivable, Related Parties, Proceeds Loans [Abstract] Loans and Leases Receivable Disclosure [Abstract] Mortgage loans held for sale Loans held for sale Allowance for loan and lease losses Ending balance Beginning balance Loans and Leases Receivable, Allowance Allowance for Loan and Lease Losses Other Real Estate Owned Loans and Leases Receivable, Real Estate Acquired Through Foreclosure, Policy [Policy Text Block] Total Loans Loans Loan portfolio based on credit risk profile Loans Net loans Loans and Leases Receivable, Net Amount Commitment to extend additional credit on loans modified in TDRs Loans and Leases Receivable, Impaired, Commitment to Lend Total mortgage loans in process Related party extensions of credit, beginning of period Related party extensions of credit, end of period Loans and Leases Receivable, Related Parties Loans and Leases Receivable, Related Parties [Roll Forward] Loans held for sale Loans Held-for-sale, Fair Value Disclosure Loans, net New loans and advances on lines of credit Loans and Leases Receivable, Related Parties, Additions Loans Loans, Notes, Trade and Other Receivables Disclosure [Text Block] Long-term debt Long-term Debt, Fair Value Long-term debt Long-term Debt Long-term debt [Abstract] Loss Contingency Nature [Axis] Loss Contingencies [Table] Loss Contingencies [Line Items] Loss Contingency, Nature [Domain] Multifamily [Member] Major Types of Debt and Equity Securities [Domain] Major Types of Debt Securities [Domain] Major Types of Debt and Equity Securities [Axis] Unconsolidated Delaware Statutory Trust Subsidiary [Member] Market Comparable Properties [Member] Market Approach Valuation Technique [Member] Investments Advertising and marketing Maturities of Time Deposits [Abstract] Maturities of Time Deposits [Abstract] Greater Than 90 Days [Member] Up to 30 Days [Member] Overnight and Continuous [Member] 30-90 Days [Member] Maximum [Member] Minimum [Member] Real Estate [Domain] Mortgage Banking and Servicing Rights [Abstract] Consumer mortgage loans secured by real estate properties for which formal foreclosure proceedings are in process Mortgage Loans in Process of Foreclosure, Amount Real Estate, Type of Property [Axis] Total losses Fair value adjustments Fair value adjustments U.S. Government Sponsored Agency Mortgage-backed Securities [Member] U.S. Government Sponsored Agency Mortgage-backed Securities [Member] Mortgage-backed Securities, Issued by US Government Sponsored Enterprises [Member] Nonperforming [Member] Net cash provided by (used in) financing activities Net Cash Provided by (Used in) Financing Activities Cash flows from financing activities [Abstract] Cash flows from financing activities: Cash flows from investing activities: Cash flows from investing activities [Abstract] Net Cash Provided by (Used in) Investing Activities [Abstract] Cash flows from operating activities [Abstract] Cash flows from operating activities: Net cash used in investing activities Net Cash Provided by (Used in) Investing Activities Net cash provided by operating activities Net Cash Provided by (Used in) Operating Activities Numerator [Abstract] Net Income (Loss) Attributable to Parent [Abstract] Net income Net income Net income New Accounting Pronouncements or Change in Accounting Principle [Table] Reduction in retained earnings New Accounting Standards New Accounting Pronouncements, Policy [Policy Text Block] New Accounting Pronouncements or Change in Accounting Principle [Line Items] Noninterest income: Noninterest bearing deposits Noninterest bearing Wholesale brokered deposits Noninterest-bearing Domestic Deposit, Brokered Noninterest expense: Total noninterest income Noninterest Income Other noninterest income Total noninterest expense Noninterest Expense Number of operating segments Occupancy, net Officer salaries and employee benefits Thereafter 2021 Operating Leases, Future Minimum Payments Receivable, in Four Years 2019 Rental expense net of rental income under operating leases Payments [Abstract] Total Operating Leases, Future Minimum Payments Due Total Operating Leases, Future Minimum Payments Receivable Thereafter Operating Leases, Future Minimum Payments Receivable, Thereafter 2018 Operating Leases, Future Minimum Payments Receivable, Current 2018 2022 2022 Operating Leases, Future Minimum Payments Receivable, in Five Years 2021 Receipts [Abstract] 2020 Operating Leases, Future Minimum Payments Receivable, in Three Years 2020 2019 Operating Leases, Future Minimum Payments Receivable, in Two Years Accounting Policies Activity for Other Real Estate Owned Other Real Estate, Roll Forward [Table Text Block] Less: Reclassification adjustments for realized gains (losses) included in net income Tax benefit Unrealized holding losses on securities available-for-sale [Abstract] Other Comprehensive Income (Loss), Available-for-sale Securities Adjustment, before Reclassification Adjustments and Tax [Abstract] Other Real Estate Owned [Abstract] Other real estate owned [Abstract] Other Real Estate [Abstract] Unrealized holding losses on securities available-for-sale: Other Comprehensive Income (Loss), Available-for-sale Securities Adjustment, before Tax, [Abstract] Other assets Other comprehensive loss: Other Comprehensive Income (Loss), Net of Tax [Abstract] Unrealized holding losses arising during the period Other Comprehensive Income (Loss), Unrealized Holding Gain (Loss) on Securities Arising During Period, before Tax Other Debt Securities [Member] Other Debt Obligations [Member] Other income Other Income Other liabilities Other real estate owned Beginning balance of other real estate owned Ending balance of other real estate owned Other Real Estate, Foreclosed Assets, and Repossessed Assets Non-cash activities: Other noninterest expense Other expenses Other Noninterest Expense Other real estate owned provision and expense Other Revenue (Expense) from Real Estate Operations Unrealized holding loss on securities available-for-sale, net of tax Unrealized holding loss on securities available-for-sale, net of tax Other Comprehensive Income (Loss), Available-for-sale Securities Adjustment, Net of Tax, Portion Attributable to Parent Other comprehensive income (loss), tax Tax benefit Other comprehensive loss, net of tax Other comprehensive loss, net of tax Performing [Member] Bank's Loan Portfolio Aging Analysis, Segregated by Class Past Due Financing Receivables [Table Text Block] Pass [Member] Parent Company [Member] Parent Company [Member] Change in loans, net Payments for (Proceeds from) Loans and Leases Dividends paid Payments of Dividends Additional investment in Federal Reserve Bank stock Payments to Acquire Federal Reserve Bank Stock Purchase of AFS securities Payments to Acquire Available-for-sale Securities Payment for investment in subsidiary Payments to Acquire Businesses and Interest in Affiliates Repurchase of common stock Payments for Repurchase of Common Stock Purchase of certificates of deposit Payments to Acquire Restricted Certificates of Deposit Purchase of premises and equipment Payments to Acquire Property, Plant, and Equipment Funding of mortgage loans held for sale Payments to Purchase Mortgage Loans Held-for-sale Performance Shares [Member] Plan Name [Axis] Plan Name [Domain] Securities pledged as collateral to secure public deposit and for other purposes Pledged Financial Instruments, Not Separately Reported, Securities Portion at Fair Value Measurement [Member] [Default] Portion at Fair Value Measurement [Member] Preferred stock, 300,000 shares authorized and unissued Preferred stock, shares authorized (in shares) Reclassifications Reclassification, Policy [Policy Text Block] Issuance of debt Advances from Federal Home Loan Bank Proceeds from Federal Home Loan Bank Borrowings Issuance of common stock Proceeds from prepayments, calls, and maturities of AFS securities Proceeds from Maturities, Prepayments and Calls of Available-for-sale Securities Proceeds from prepayments and maturities of HTM securities Issuance of capital securities in a private placement Proceeds from sales of AFS securities Proceeds from sale of mortgage loans held for sale Proceeds from sale of other real estate owned and repossessed assets Cash received from option exercises under all share-based payment arrangements for the year Proceeds from sale and retirement of premises and equipment Proceeds from Sale of Property, Plant, and Equipment Professional fees Premises and Equipment Schedule of Premises and Equipment Premises and Equipment [Abstract] Premises and equipment, net Premises and equipment, net Premises and equipment, gross Property, Plant and Equipment, Gross Premises and Equipment Property, Plant and Equipment Disclosure [Text Block] Property, Plant and Equipment, Net, by Type [Abstract] Property, Plant and Equipment [Line Items] Estimated useful life Property, Plant and Equipment, Type [Axis] Property, Plant and Equipment, Type [Domain] Provision for loan losses Provision for loan losses Provision charged to expense Range [Domain] Range [Axis] Total foreclosed properties Real Estate [Member] Real Estate Loan [Member] Sale of assets SEC Schedule III, Real Estate, Cost of Real Estate Sold Other Real Estate Owned Other Real Estate Owned [Abstract] Loans [Abstract] Loans held for sale [Abstract] Amounts Reclassified from Accumulated Other Comprehensive Income (AOCI) Reclassification out of Accumulated Other Comprehensive Income [Table Text Block] Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items] Reclassification Out of Accumulated Other Comprehensive Income [Member] Reclassification out of Accumulated Other Comprehensive Income [Table] Reclassification out of Accumulated Other Comprehensive Income [Domain] Reclassification out of Accumulated Other Comprehensive Income [Axis] Activity for other real estate owned [Roll Forward] SEC Schedule III, Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] Regulatory Matters [Abstract] Regulatory Matters Regulatory Capital Requirements under Banking Regulations [Text Block] Related Party Transaction [Line Items] Related Party [Domain] Related party deposit Related Party [Axis] Total payment to related party Related Party Transaction, Selling, General and Administrative Expenses from Transactions with Related Party Related Party Transactions Related Party Transactions Disclosure [Text Block] Related Party Transactions [Abstract] Expenses Related Party Transaction, Expenses from Transactions with Related Party Payments on advances from Federal Home Loan Bank Repayments of Federal Home Loan Bank Borrowings Repayment of debt Debt instrument, purchase price Repurchase of long-term debt Repayments of Long-term Debt Counterparty Name [Domain] Repurchase Agreements Repurchase Agreements, Resale Agreements, Securities Borrowed, and Securities Loaned Disclosure [Text Block] Residential [Member] Residential [Member] Restricted Stock [Member] Retained earnings Retained Earnings [Member] Retirement Plan Name [Domain] Retirement Plan Name [Axis] Total income Revenues Income [Abstract] Revolving Credit Promissory Note [Member] Total capital (to risk-weighted assets), Ratio [Abstract] Concentrations of Credit Risk [Abstract] Substandard [Member] Vested (in dollars per share) Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested, Weighted Average Grant Date Fair Value Expected option life Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Term Vested (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested, Number of Shares Nonvested, beginning of period (in dollars per share) Nonvested, end of period (in dollars per share) Share-based Compensation Arrangement by Share-based Payment Award, Options, Nonvested, Weighted Average Grant Date Fair Value Forfeited (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Options, Nonvested Options Forfeited, Number of Shares Grant date fair value of shares vested for the year Nonvested options, weighted average grant date fair value [Abstract] Intrinsic value of options exercisable Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Intrinsic Value Forfeited (in dollars per share) Share-based Compensation Arrangement by Share-based Payment Award, Options, Nonvested Options Forfeited, Weighted Average Grant Date Fair Value Nonvested, beginning of period (in shares) Nonvested, end of period (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Options, Nonvested, Number of Shares Nonvested options, number of shares [Roll Forward] Weighted average remaining contractual term Maximum balance for repurchase agreements at any month-end Average balance of repurchase agreements Other salaries and employee benefits Compensation Scenario, Unspecified [Domain] Plan [Member] Scenario, Plan [Member] Forecast [Member] Condensed Statements of Income and Comprehensive Income Schedule of Stock Option Activity Components of Net Deferred Tax Liability Activity for Related Party Transactions Schedule of Related Party Transactions [Table Text Block] Schedule of Financing Receivables Past Due [Table] Schedule of Financing Receivables Past Due [Table] Schedule of Financing Receivable, Allowance for Credit Losses [Table] Schedule of Financing Receivable, Allowance for Credit Losses [Table] Activity to Core Deposit Intangible Condensed Balance Sheets Computation of Basic and Diluted Earnings per Share Schedule of Finite-Lived Intangible Assets [Table] Condensed Statements of Cash Flows Schedule of Financing Receivable, Recorded Investment, Credit Quality Indicator [Table] Reconciliation of Income Tax Expense at Statutory Rate to Actual Income Tax Expense Available for Sale Securities and Held-to-Maturity Securities, Continuous Unrealized Loss Position Schedule of Unrealized Loss on Investments [Table Text Block] Nonaccrual Loans Segregated by Class of Loans Schedule of Financing Receivable, Troubled Debt Restructurings [Table] Schedule of Restricted Stock Activity Schedule of Impaired Financing Receivable [Table] Summary for Status of Nonvested Options Schedule of Weighted Average Assumptions Used for Estimating Grant-Date Fair Value of Each Option Grant Schedule of Minimum Non-Cancellable Rental Payments and Rental Receipts Components of Provision for Income Taxes Schedule of Cash and Cash Equivalents [Table] Summary of Amortized Cost and Fair Value of Available-for-sale Securities Schedule of Available-for-sale Securities Reconciliation [Table Text Block] Unrecognized Compensation Cost, Grant-Date Fair Value of Shares Vested, Cash Received from Option Exercises and Actual Tax Benefit Realized for Tax Deductions from Option Exercises Share-based Compensation, Activity [Table Text Block] Schedule of Compliance with Regulatory Capital Requirements under Banking Regulations [Table] Schedule of Available-for-sale Securities [Table] Schedule of Available-for-sale Securities [Table] Schedule of Long-term Debt Capital Amounts and Ratios Schedule of Available for Sale Securities [Line Items] Condensed Financial Statements [Table] Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share [Table] Schedule of Employee Stock Ownership Plan (ESOP) Disclosures [Table] Schedule of Fair Value, Off-balance Sheet Risks [Table] Schedule of Held-to-maturity Securities [Line Items] Off-Balance Sheet Financial Instruments Schedule of Federal Home Loan Bank Advances Schedule of Held-to-maturity Securities [Table] Remaining Contractual Maturity of Securities Sold Under Agreements to Repurchase by Class of Collateral Pledged Schedule of Repurchase Agreements [Table Text Block] Schedule of Related Party Transactions, by Related Party [Table] Property, Plant and Equipment [Table] Property, Plant and Equipment [Table] Schedule of Short-term Debt [Table] Schedule of Short-term Debt Schedule of Financial Instruments Subject to Mandatory Redemption by Settlement Terms [Axis] Activity for Capitalized Mortgage Servicing Rights Using Fair Value Method