Accounting Policies [Abstract] Summary of Significant Accounting Policies Basis of Presentation and Significant Accounting Policies [Text Block] Derivative Instruments and Hedging Activities Disclosure [Abstract] Derivative [Table] Derivative [Table] Derivative, by Nature [Axis] Derivative Instrument [Axis] Derivative, Name [Domain] Derivative Contract [Domain] Interest Rate Lock Commitments Interest Rate Lock Commitments [Member] Forward Commitments Forward Contracts [Member] Interest Rate Swap Agreements Interest Rate Swap [Member] Foreign Exchange Contracts Foreign Exchange Contract [Member] Derivative Financial Instruments Not Designated as Hedging Instruments Derivatives, Fair Value [Line Items] Asset Derivatives Derivative Instruments Not Designated as Hedging Instruments, Asset, at Fair Value Liability Derivatives Derivative Instruments Not Designated as Hedging Instruments, Liability, at Fair Value Fair Value Disclosures [Abstract] Fair Value Measurements, Recurring and Nonrecurring [Table] Fair Value Measurements, Recurring and Nonrecurring [Table] Measurement Frequency [Axis] Measurement Frequency [Axis] Fair Value, Measurement Frequency [Domain] Fair Value, Measurement Frequency [Domain] Fair Value, Hierarchy [Axis] Fair Value, Hierarchy [Axis] Fair Value Hierarchy [Domain] Fair Value Hierarchy [Domain] Significant Other Unobservable Inputs (Level 3) Fair Value, Inputs, Level 3 [Member] Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] Mortgage Servicing Rights accounted for under the amortization method Servicing Asset at Amortized Cost Investments, Debt and Equity Securities [Abstract] Schedule of amortized cost, gross unrealized gains and losses, and fair value of investment securities Schedule of Available For Sale Securities and Held To Maturity [Table Text Block] This item represents the entire disclosure related to reconciling the amortized cost basis and aggregate fair value of the entity's available-for-sale and held-to-maturity investment securities. Analysis of the contractual maturities of investment securities Investments Classified by Contractual Maturity Date [Table Text Block] Schedule of gains (losses) on sale of investment securities Gain (Loss) on Investments [Table Text Block] Schedule of investment securities in an unrealized loss position Schedule of Unrealized Loss on Investments [Table Text Block] Schedule of interest income from taxable and non-taxable investment securities Interest Income From Taxable And Non-Taxable Investment Securities [Table Text Block] Interest income from taxable and non-taxable investment securities. Schedule of carrying value of company's Federal Home Loan Bank and Federal Reserve Bank Schedule of Carrying Value of Company's Federal Home Loan Bank and Federal Reserve Bank [Table Text Block] Schedule of Carrying Value of Company's Federal Home Loan Bank and Federal Reserve Bank [Table Text Block] Revenue from Contract with Customer [Abstract] Revenue from Contract with Customer [Abstract] Disaggregation of Revenue [Table] Disaggregation of Revenue [Table] Disaggregation of Revenue [Table] Adjustments for New Accounting Pronouncements [Axis] Adjustments for New Accounting Pronouncements [Axis] Type of Adoption [Domain] Type of Adoption [Domain] Accounting Standards Update 2014-09 Accounting Standards Update 2014-09 [Member] Products and Services [Axis] Products and Services [Axis] Products and Services [Domain] Products and Services [Domain] Noninterest Income In Scope of Topic 606 Noninterest Income In Scope of Topic 606 [Member] Noninterest Income In Scope of Topic 606 [Member] Noninterest Income Out of Scope of Topic 606 Noninterest Income Out of Scope of Topic 606 [Member] Noninterest Income Out of Scope of Topic 606 [Member] Disaggregation of Revenue [Line Items] Disaggregation of Revenue [Line Items] [Line Items] for Disaggregation of Revenue [Table] Trust and Asset Management Fees and Commissions, Fiduciary and Trust Activities Service Charges on Deposit Accounts Service Charges on Deposit Accounts Includes amounts charged depositors for: (1) maintenance of their accounts (maintenance charges); (2) failure to maintain specified minimum balances on account; (3) exceeding the number of checks or transactions allowed to be processed in a given period; (4) checks drawn on no minimum balance deposit accounts; (5) withdrawals from nontransaction deposit accounts; (6) closing savings accounts before a specified minimum period of time has elapsed; (7) accounts which have remained inactive for extended periods of time or which have become dormant; (8) checks drawn against insufficient funds that the bank assesses regardless of whether it decides to pay, return or hold the check; (9) issuing stop payment orders; (10) certifying checks; (11) accumulating or disbursing funds deposited in IRAs or Keogh Plan accounts when not handled by the bank's trust department; and (12) penalties assessed on the early withdrawal of time deposits. Excludes amounts charged depositors for use of automated teller machines or remote service units. Fees, Exchange, and Other Service Charges Fees, Exchange, and Other Service Charges The noninterest income derived from the following: (1) fees and services from debit card services; (2) fees charged depositors for use of automated teller machines; (3) merchant service activity; (4) annual fees from loans; (5) other fees and service charges. Annuity and Insurance Insurance Commissions and Fees Other Noninterest Income, Other Operating Income Noninterest Income Noninterest Income Statement [Table] Statement [Table] Accounting Standards Update 2018-02 Accounting Standards Update 2018-02 [Member] Accounting Standards Update 2018-02 [Member] Statement [Line Items] Statement [Line Items] Reclassification from AOCI Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax Retained Earnings Retained Earnings (Accumulated Deficit) Income tax effects allocated to equity Income Tax Effects Allocated Directly to Equity, Cumulative Effect of Change in Accounting Principle Commitments and Contingencies Disclosure [Abstract] Commitments, Contingencies, and Guarantees Commitments Contingencies and Guarantees [Text Block] Variable Interest Entity, Not Primary Beneficiary, Disclosures [Abstract] Schedule of Variable Interest Entities [Table] Schedule of Variable Interest Entities [Table] Variable Interest Entities [Axis] Variable Interest Entities [Axis] Variable Interest Entity, Classification [Domain] Variable Interest Entity, Classification [Domain] Low-income housing partnerships Low-income housing partnerships [Member] Low-income housing partnerships [Member] Solar energy partnerships Solar energy partnerships [Member] Solar energy partnerships [Member] Balance Sheet Location [Axis] Balance Sheet Location [Axis] Balance Sheet Location [Domain] Balance Sheet Location [Domain] Other Assets Other Assets [Member] Other Liabilities Other Liabilities [Member] Variable Interest Entity [Line Items] Variable Interest Entity [Line Items] Period over which tax credits or benefits are generally recognized (in years) Variable Interest Entities Tax Credit or Benefit Recognition Period Represents the period over which tax credits or benefits arising from variable interest entities are recognized. Unfunded commitments to fund low-income housing partnerships Qualified Affordable Housing Project Investments, Commitment Variable Interest Entity, Nonconsolidated, Carrying Amount, Assets Variable Interest Entity, Nonconsolidated, Carrying Amount, Assets Transfers and Servicing of Financial Assets [Abstract] Schedule of Assumptions for Fair Value as of Balance Sheet Date of Assets or Liabilities that relate to Transferor's Continuing Involvement [Table] Schedule of Assumptions for Fair Value as of Balance Sheet Date of Assets or Liabilities that relate to Transferor's Continuing Involvement [Table] Financial Instrument [Axis] Financial Instrument [Axis] Types of Financial Instruments [Domain] Financial Instruments [Domain] Mortgage Servicing Rights Servicing Contracts [Member] Key data and assumptions used in estimating the fair value of mortgage servicing rights Assumption for Fair Value as of Balance Sheet Date of Assets or Liabilities that relate to Transferor's Continuing Involvement [Line Items] Weighted-Average Constant Prepayment Rate (as a percent) Assumption for Fair Value of Assets or Liabilities that relate to Transferor's Continuing Involvement, Prepayment Speed Weighted-Average Life (in years) Assumption for Fair Value of Assets or Liabilities that relate to Transferor's Continuing Involvement, Weighted Average Life Weighted-Average Note Rate (as a percent) Assumption for Fair Value of Interests Continued to be Held by Transferor, Servicing Assets or Liabilities Note Rate The weighted average note rate of securitized assets. This is used as a key input in measuring the fair value of assets or liabilities that relate to a transferor's continuing involvement, if any, as of the date of the latest statement of financial position presented. Weighted-Average Discount Rate (as a percent) Assumption for Fair Value of Assets or Liabilities that relate to Transferor's Continuing Involvement, Discount Rate Schedule of Available-for-sale Securities [Table] Schedule of Available-for-sale Securities [Table] Major Types of Debt and Equity Securities [Axis] Major Types of Debt and Equity Securities [Axis] Major Types of Debt and Equity Securities [Domain] Major Types of Debt and Equity Securities [Domain] Debt Securities Issued by Government Agencies US Government Agencies Debt Securities [Member] Residential - Government Agencies Residential Mortgage-Backed Securities issued by U.S. government agencies [Member] Debt securities collateralized by residential real estate mortgage loans issued by U.S. government agencies such as the Government National Mortgage Association (GNMA) [Member] Residential - U.S. Government-Sponsored Enterprises Residential Mortgage-Backed Securities Issued by U.S. Government Sponsored Enterprises [Member] Debt securities collateralized by residential real estate mortgage loans issued by U.S. government-sponsored enterprises. [Member] Commercial - Government Agencies Commercial Mortgage-Backed Securities Issued by Government Agencies [Member] Debt securities collateralized by commercial real estate mortgage loans issued by U.S. government agencies such as the Government National Mortgage Association (GNMA) [Member] Mortgage-Backed Securities Collateralized Mortgage Backed Securities [Member] Schedule of Available-for-sale Securities [Line Items] Schedule of Available-for-sale Securities [Line Items] Investment Securities Available-for-Sale, Debt Maturities (Abstract): Available-for-sale Securities, Debt Maturities [Abstract] Available-for-sale Securities, Debt Maturities, Single Maturity Date, Amortized Cost Basis Rolling Maturity[Abstract] Available-for-sale Securities, Debt Maturities, Single Maturity Date, Amortized Cost Basis, Rolling Maturity [Abstract] Due in One Year or Less Available-for-sale Securities, Debt Maturities, Next Rolling Twelve Months, Amortized Cost Basis Due After One Year Through Five Years Available-for-sale Securities, Debt Maturities, Rolling Year Two Through Five, Amortized Cost Basis Due After Five Years Through Ten Years Available-for-sale Securities, Debt Maturities, Rolling Year Six Through Ten, Amortized Cost Basis Due After Ten Years Available-for-sale Securities, Debt Maturities, Rolling after Year Ten, Amortized Cost Basis Amortized Cost, Total Available-for-sale Securities, Debt Maturities, Single Maturity Date, Amortized Cost Basis Available-for-sale Securities, Debt Maturities, Single Maturity Date, Rolling Maturities [Abstract] Available-for-sale Securities, Debt Maturities, Single Maturity Date, Rolling Maturity [Abstract] Due in One Year or Less Available-for-sale Securities, Debt Maturities, Next Rolling Twelve Months, Fair Value Due After One Year Through Five Years Available-for-sale Securities, Debt Maturities, Rolling Year Two Through Five, Fair Value Due After Five Years Through Ten Years Available-for-sale Securities, Debt Maturities, Rolling Year Six Through Ten, Fair Value Due After Ten Years Available-for-sale Securities, Debt Maturities, Rolling after Year Ten, Fair Value Fair Value, Total Available-for-sale Securities, Debt Maturities, Single Maturity Date Available-for-sale Securities, Debt Securities Issued by Government Agencies and Mortgage-Backed Securities: Amortized Cost Available-for-sale Securities, Debt Maturities, without Single Maturity Date, Amortized Cost Basis Available-for-sale Securities, Debt Securities Issued by Government Agencies and Mortgage-Backed Securities: Fair Value Available-for-sale Securities, Debt Maturities, without Single Maturity Date, Fair Value Available-for-Sale: Amortized Cost Available-for-sale Securities, Amortized Cost Basis Available-for-Sale: Fair Value Available-for-sale Securities Schedule of Held-to-maturity Securities [Table] Schedule of Held-to-maturity Securities [Table] Debt Security [Axis] Debt Security [Axis] Major Types of Debt Securities [Domain] Major Types of Debt Securities [Domain] Mortgage-Backed Securities Schedule of Held-to-maturity Securities [Line Items] Schedule of Held-to-maturity Securities [Line Items] Investment Securities Held-to-Maturity, Debt Maturities (Abstract) Held-to-maturity Securities, Debt Maturities [Abstract] Held-to-maturity Securities, Debt Maturities, Single Maturity Date, Amortized Cost Basis, Rolling Maturities (Abstract] Held-to-maturity Securities, Debt Maturities, Single Maturity Date, Amortized Cost, Rolling Maturity [Abstract] Due in One Year or Less Held-to-maturity Securities, Debt Maturities, Next Rolling Twelve Months, Amortized Cost Due After One Year Through Five Years Held-to-maturity Securities, Debt Maturities, Rolling Year Two Through Five, Amortized Cost Due After Five Years Through Ten Years Held-to-maturity Securities, Debt Maturities, Rolling Year Six Through Ten, Amortized Cost Due After Ten Years Held-to-maturity Securities, Debt Maturities, Rolling after Ten Years, Amortized Cost Amortized Cost, Total Held-to-maturity Securities, Debt Maturities, Single Maturity Date, Amortized Cost Basis Held-to-Maturity Securities, Debt Maturities, Single Maturity Date, Fair Value, Rolling Maturities [Abstract] Held-to-maturity Securities, Debt Maturities, Single Maturity Date, Fair Value, Rolling Maturity [Abstract] Due in One Year or Less Held-to-maturity Securities, Debt Maturities, Next Rolling Twelve Months, Fair Value Due After One Year Through Five Years Held-to-maturity Securities, Debt Maturities, Rolling Year Two Through Five, Fair Value Due After Five Years Through Ten Years Held-to-maturity Securities, Debt Maturities, Rolling Year Six Through Ten, Fair Value Due After Ten Years Held-to-maturity Securities, Debt Maturities, Rolling after Ten Years, Fair Value Fair Value, Total Held-to-maturity Securities, Debt Maturities, Single Maturity Date, Fair Value Held-to-Maturity: Mortgage-Backed Securities: Amortized Cost Held-to-maturity Securities, Debt Maturities, without Single Maturity Date, Net Carrying Amount Held-to-Maturity: Mortgage-Backed Securities: Fair Value Held-to-maturity Securities, Debt Maturities, without Single Maturity Date, Fair Value Held-to-Maturity: Amortized Cost Held-to-maturity Securities, Amortized Cost before Other than Temporary Impairment Held-to-Maturity: Fair Value Held-to-maturity Securities, Fair Value Carrying value of investment securities which were pledged to secure deposits of gov't entities and repos Carrying Value of Investment Securities Pledged The carrying value, as of the date of each statement of financial position presented, of investment securities, classified as available for sale or held to maturity, which are owned but transferred to serve as collateral to secure deposits of government entities and securities sold under agreements to repurchase, and payment of the related debt obligation, primarily a secured borrowing or repurchase agreement. Loans and Leases and Allowance for Loan and Lease Losses [Abstract] Loans and Leases and Allowance for Loan and Lease Losses Consumer mortgage loans collateralized by residential real estate property that are in the process of foreclosure Mortgage Loans in Process of Foreclosure, Amount Schedule of Financing Receivable, Troubled Debt Restructurings [Table] Schedule of Financing Receivable, Troubled Debt Restructurings [Table] Financing Receivable Portfolio Segment [Axis] Financing Receivable Portfolio Segment [Axis] Financing Receivable Portfolio Segment [Domain] Financing Receivable Portfolio Segment [Domain] Commercial Commercial Portfolio Segment [Member] Consumer Consumer Portfolio Segment [Member] Class of Financing Receivable, Type [Axis] Class of Financing Receivable, Type [Axis] Class of Financing Receivable, Type [Domain] Class of Financing Receivable, Type [Domain] Commercial and Industrial Commercial and Industrial [Member] Class of financing receivables related to commercial and industrial financing receivables. Commercial Mortgage Commercial Real Estate [Member] Residential Mortgage Residential Mortgage [Member] Home Equity Home Equity Line of Credit [Member] Automobile Automobile Loan [Member] Other Consumer Loan [Member] Range [Axis] Range [Axis] Range [Domain] Range [Domain] Minimum Minimum [Member] Information related to loans modified as a TDR Financing Receivable, Modifications [Line Items] Default Period Past Due Following Modification of Loans in TDR (in days) Financing Receivable Modifications Made Default Period Represents the number of days past due following modification of loans in a troubled debt restructuring, when a loan is considered to be in default. Number of Contracts, TDRs that Defaulted Financing Receivable, Modifications, Subsequent Default, Number of Contracts Recorded Investment (as of period ended), TDRs that Defaulted Financing Receivable, Modifications, Subsequent Default, Recorded Investment Statement of Comprehensive Income [Abstract] Net Income Net Income (Loss) Attributable to Parent Other Comprehensive Income (Loss), Net of Tax: Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent [Abstract] Net Unrealized Gains (Losses) on Investment Securities Net Unrealized Gain/Loss on Investment Securities, net of tax Amount after tax and reclassification adjustments or gain or loss in value of unsold Available- for-Sale securities and amortization of Available-for-Sale holding gains moved to Held-to-Maturity. Defined Benefit Plans Other Comprehensive (Income) Loss, Pension and Other Postretirement Benefit Plans, Adjustment, Net of Tax, Portion Attributable to Parent Total Other Comprehensive Income (Loss) Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent Comprehensive Income Comprehensive Income (Loss), Net of Tax, Attributable to Parent Offsetting [Abstract] Schedule of Repurchase Agreements - by maturity date and collateral type Schedule of Repurchase Agreements [Table Text Block] Schedule of assets and liabilities subject to an enforceable master netting arrangement Offsetting Assets and Liabilities [Table Text Block] Offsetting Assets and Liabilities [Table Text Block] Earnings Per Share [Abstract] Reconciliation of the weighted average number of common shares outstanding for computing diluted earnings per share and antidilutive stock options and restricted stock outstanding Schedule of Earnings Per Share, Basic and Diluted [Table Text Block] Comprehensive Income (Loss), Net of Tax, Attributable to Parent [Abstract] Components of other comprehensive income Comprehensive Income (Loss) [Table Text Block] Schedule of accumulated other comprehensive income (loss) Schedule of Accumulated Other Comprehensive Income (Loss) [Table Text Block] Reclassification out of accumulated other comprehensive income Reclassification out of Accumulated Other Comprehensive Income [Table Text Block] Equity Method Investments and Joint Ventures [Abstract] Equity Method Investments Equity Method Investments [Table Text Block] Compensation and Retirement Disclosure [Abstract] Schedule of Defined Benefit Plans Disclosures [Table] Schedule of Defined Benefit Plans Disclosures [Table] Defined Benefit Plans and Other Postretirement Benefit Plans Disclosures [Axis] Defined Benefit Plans and Other Postretirement Benefit Plans [Axis] Defined Benefit Plans and Other Postretirement Benefit Plans [Domain] Defined Benefit Plan and Other Postretirement Benefit Plan [Domain] Pension Benefits Pension Plan [Member] Postretirement Benefits Other Postretirement Benefit Plan [Member] Defined benefit pension plan disclosure Defined Benefit Plan Disclosure [Line Items] Net periodic benefit cost for pension plans and the postretirement benefit plan Defined Benefit Plan, Net Periodic Benefit Cost [Abstract] Service Cost Defined Benefit Plan, Service Cost Interest Cost Defined Benefit Plan, Interest Cost Expected Return on Plan Assets Defined Benefit Plan, Expected Return on Plan Assets Amortization of Prior Service Credit Defined Benefit Plan, Amortization of Prior Service Cost (Credit) Amortization of Net Actuarial Losses (Gains) Defined Benefit Plan, Amortization of Gains (Losses) Net Periodic Benefit Cost Defined Benefit Plan, Net Periodic Benefit Cost Employer Contributions Defined Benefit Plan, Contributions by Employer Estimated Future Employer Contributions in Current Fiscal Year Defined Benefit Plans, Estimated Future Employer Contributions in Current Fiscal Year Derivative Financial Instruments Derivative Instruments and Hedging Activities Disclosure [Text Block] Earnings Per Share Earnings Per Share [Text Block] Segment Reporting [Abstract] Business Segments Segment Reporting Disclosure [Text Block] Cash and Cash Equivalents [Abstract] Schedule of Cash and Cash Equivalents Schedule of Cash and Cash Equivalents [Table Text Block] Fair Value, Mortgage Servicing Rights Measured on Recurring Basis, Unobservable Input Reconciliation [Roll Forward] Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] Fair Value, Mortgage Servicing Rights, Beginning Balance Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value Fair Value, Mortgage Servicing Rights, Realized and Unrealized Net Gains (Losses) Included in Net Income Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Earnings Fair Value, Mortgage Servicing Rights, Ending Balance Fair Value, Mortgage Service Rights, Total Unrealized Net Gains (Losses) Included in Net Income Related to Assets Still Held Fair Value, Assets Measured on Recurring Basis, Change in Unrealized Gain (Loss) Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Roll Forward] Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Roll Forward] Fair Value, Net Derivative Assets and Liabilities, Beginning Balance Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis with Unobservable Inputs Fair Value, Net Derivative Assets and Liabilities, Realized and Unrealized Net Gains (Losses) Included in Net Income Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Inputs Reconciliation, Gain (Loss) Included in Earnings Fair Value, Net Derivative Assets and Liabilities, Transfers to Loans Held for Sale Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Inputs Reconciliation, Transfers to Loans Held For Sale This element represents transfers to loans held for sale which have taken place during the period in relation to assets measured at fair value on a recurring basis using unobservable inputs (Level 3). Variation margin payments for swap liabilities Variation margin payments for swap liabilities Variation margin payments for swap liabilities Fair Value, Net Derivative Assets and Liabilities, Ending Balance Fair Value, Net Derivative Assets and Liabilities,Total Unrealized Net Gains (Losses) Included in Net Income Related to Assets Still Held Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Inputs Reconciliation, Unrealized Gain (Loss) Included in Net Income Related to Assets Still Held Amount of unrealized (holding) gain (loss) which is included in the statement of income (or changes in net assets) related to those net derivative assets still held at the reporting date for which fair value is measured on a recurring basis using significant unobservable inputs (Level 3). Statement of Financial Position [Abstract] Common Stock, par value (in dollars per share) Common Stock, Par or Stated Value Per Share Common Stock, authorized shares Common Stock, Shares Authorized Common Stock, issued shares Common Stock, Shares, Issued Common Stock, outstanding shares Common Stock, Shares, Outstanding Treasury Stock, Shares Treasury Stock, Shares Loans and Leases and the Allowance for Loan and Lease Losses Loans and Leases and Allowance for Loan and Lease Losses [Text Block] The disclosure of Loans and Leases and the Allowance for Loan and Lease Losses includes: (1) balances in the entity's classes of loans and leases as of period end; (2) roll forward of the entity's Allowance for Loan and Lease Losses by portfolio segment; (3) balances in the entity's classes of loans and leases by internal credit quality indicators as of period end; (4) an aging analysis of the entity's classes of loans and leases as of period end; (5) balances of impaired loans by the entity's classes of loans as of period end; and (6) information related to the average recorded investment and interest income recognized on impaired loans for the periods presented. Investment Securities Investments in Debt and Marketable Equity Securities (and Certain Trading Assets) Disclosure [Text Block] Fair Value, Option, Quantitative Disclosures [Table] Fair Value, Option, Quantitative Disclosures [Table] Residential mortgage loans held for sale Residential Mortgage Held For Sale [Member] A loan to an individual to purchase or refinance residential real estate such as a home, in which the real estate itself serves as collateral for the loan, that will be sold to other entities. Fair Value Option Fair Value, Option, Quantitative Disclosures [Line Items] Aggregate Fair Value Loans Held-for-sale, Fair Value Disclosure Aggregate Unpaid Principal Fair Value Option Loans Held for Sale Aggregate Unpaid Principal Represents the aggregate unpaid principal balance of loans held for sale for which the fair value option was elected. Aggregate Fair Value Less Aggregate Unpaid Principal Fair Value, Option, Aggregate Differences, Loans and Long-term Receivables Financial Instruments Owned and Pledged as Collateral [Table] Financial Instruments Owned and Pledged as Collateral [Table] Repurchase Agreements and Similar Transactions, Maturity Periods [Axis] Repurchase Agreements and Similar Transactions, Maturity Periods [Axis] Repurchase Agreements and Similar Transactions, Maturity Periods [Domain] Repurchase Agreements and Similar Transactions, Maturity Periods [Domain] Maturity Up To 90 Days [Member] Maturity Up To 90 Days [Member] Maturity Up To 90 Days [Member] Maturity 91 To 365 Days [Member] Maturity 91 To 365 Days [Member] Maturity 91 To 365 Days [Member] Maturity 1 To 3 Years [Member] Maturity 1 To 3 Years [Member] Maturity 1 To 3 Years [Member] Maturity After 3 Years [Member] Maturity After 3 Years [Member] Maturity After 3 Years [Member] Financial Instruments Owned and Pledged as Collateral by Type [Axis] Financial Instruments Owned and Pledged as Collateral by Type [Axis] Financial Instruments Owned and Pledged as Collateral, Type [Domain] Financial Instruments Owned and Pledged as Collateral, Type [Domain] Debt Securities Issued by the U.S. Treasury and Government Agencies Debt Securities Issued by United States Treasury and Government Agencies [Member] This category includes investments in debt securities issued by the United States Department of the Treasury and U.S. Government Agencies. Such securities may include treasury bills (short-term maturities - one year or less), treasury notes (intermediate term maturities - two to ten years), treasury bonds (long-term maturities - ten to thirty years), and debt securities issued by the Government National Mortgage Association (Ginnie Mae). Debt Securities Issued by States and Political Subdivisions US States and Political Subdivisions Debt Securities [Member] Mortgage-Backed Securities: Residential - Government Agencies Mortgage-Backed Securities: Residential - U.S. Government-Sponsored Enterprises Securities Sold Under Agreements to Repurchase Assets Sold under Agreements to Repurchase [Line Items] Securities Sold under Agreements to Repurchase Securities Sold under Agreements to Repurchase, Gross Low Income Housing Tax Credit Partnerships Affordable Housing Program [Text Block] Schedule of Financing Receivable, Recorded Investment, Credit Quality Indicator [Table] Schedule of Financing Receivable, Recorded Investment, Credit Quality Indicator [Table] Construction Construction Loans [Member] Lease Financing Finance Leases Portfolio Segment [Member] Financing Receivable Information by Credit Quality Indicator [Axis] Internal Credit Assessment [Axis] Financing Receivable, by Credit Quality Indicator [Domain] Internal Credit Assessment [Domain] Pass Pass [Member] Special Mention Special Mention [Member] Classified Substandard [Member] Recorded Investment in Loans and Leases by Class and by Credit Quality Indicator Financing Receivable, Recorded Investment [Line Items] Number of days past due for loans and leases in classified credit quality indicator Financing Receivable, Number of Days Past Due for Loans and Leases, to be Classified as Classified Credit quality Indicator Represents the number of days past due for loans and leases to be classified as classified credit quality indicator. Maximum current loan-to-value ratio for residential mortgage and home equity loans to be considered as pass (as a percent) Financing Receivable, Credit Quality Current Loan to Value Ratio Percentage, Maximum Represents the maximum current loan-to-value ratio for residential mortgage and home equity loans to be considered as pass. Number of months up to which residential and home equity loans may be considered classified, even if they are current as to principal and interest Financing Receivable, Modified Residential Mortgage and/or Home Equity Loans, Maximum Number of Months Categorized as Classified Credit Quality Indicator If Principal and Interest are Current Number of months up to which residential mortgage and home equity loans may be considered classified, even if they are current as to principal and interest. Following a period of demonstrated performance in accordance with contractual terms, the loan may be removed. Total Recorded Investment in Loans and Leases Loans and Leases Receivable, Net of Deferred Income Mortgage Servicing Rights Transfers and Servicing of Financial Assets [Text Block] Schedule of Loan and Lease Portfolio Schedule of Aggregate Carrying Amount of Loans and Leases [Table Text Block] Tabular disclosure of the aggregate carrying amount of all categories of loans and leases held in portfolio, net of unearned income, net of deferred loan fees or costs, and any direct principal charge-offs. Schedule of Portfolio Segment and Balance in Allowance Disaggregated on the Basis of Impairment Measurement Method Allowance for Credit Losses on Financing Receivables [Table Text Block] Schedule of Recorded Investment in Loans and Leases by Class and by Credit Quality Indicator Financing Receivable Credit Quality Indicators [Table Text Block] Schedule of Aging Analysis by Class of Loan and Lease Portfolio Past Due Financing Receivables [Table Text Block] Schedule of Information Related to Impaired Loans Impaired Financing Receivables [Table Text Block] Schedule of the Average Recorded Investment and Interest Income Recognized on Impaired Loans Schedule of Average Recorded Investment and Interest Income Recognized on Impaired Loans [Table Text Block] Tabular disclosure of the average recorded investment and interest income recognized on impaired financing receivables. Schedule of Loans Modified in a TDR and TDRs that Defaulted During the Period Within 12 mos of Modification Date Troubled Debt Restructurings on Financing Receivables [Table Text Block] Disaggregation of Revenue Disaggregation of Revenue [Table Text Block] Disaggregation of Revenue [Table Text Block] Credit Rating, Moody's [Axis] Credit Rating, Moody's [Axis] External Credit Rating, Moody's [Domain] External Credit Rating, Moody's [Domain] Moody's, Aa2 or Better Rating Moody's, Aa2 or Better Rating [Member] Moody's, Aa2 or Better Rating [Member] Concentration Risk Benchmark [Axis] Concentration Risk Benchmark [Axis] Concentration Risk Benchmark [Domain] Concentration Risk Benchmark [Domain] Municipal Debt Securities Municipal Debt Securities [Member] Municipal Debt Securities [Member] Hawaiian Municipal Debt Securities Hawaiian Municipal Debt Securities [Member] Hawaiian Municipal Debt Securities [Member] Concentration Risk Type [Axis] Concentration Risk Type [Axis] Concentration Risk Type [Domain] Concentration Risk Type [Domain] Geographic Concentration Risk Geographic Concentration Risk [Member] Investment Concentration Risk Investment Concentration Risk [Member] Investment Concentration Risk [Member] Investment Geographic Region [Axis] Investment Geographic Region [Axis] Investment Geographic Region [Domain] Investment Geographic Region [Domain] HAWAII HAWAII General Obligation Bond General Obligation Bond [Member] General Obligation Bond [Member] Debt Securities Issued by State and Political Subdivision, State of Hawaii Investments, Fair Value Disclosure Concentration Risk, Percentage Concentration Risk, Percentage Municipal Debt Securities Issued by One Single State or Political Subdivision as Percentage of Total Fair Value of Entire Municipal Debt Securities Threshold Municipal Debt Securities Issued by One Single State or Political Subdivision as Percentage of Total Fair Value of Entire Municipal Debt Securities Threshold Municipal Debt Securities Issued by One Single State or Political Subdivision as Percentage of Total Fair Value of Entire Municipal Debt Securities Threshold Debt Securities Issued by Corporations Corporate Debt Securities [Member] Available-for-sale Securities, Continuous Unrealized Loss Position [Abstract] Available-for-sale Securities, Continuous Unrealized Loss Position [Abstract] Less Than 12 Months, Fair Value Available-for-sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value Less Than 12 Months, Gross Unrealized Losses Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss 12 Months or Longer, Fair Value Available-for-sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value 12 Months or Longer, Gross Unrealized Losses Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss Total Fair Value Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value Total Gross Unrealized Losses Available-for-sale Securities, Continuous Unrealized Loss Position, Accumulated Loss Held-to-maturity Securities, Continuous Unrealized Loss Position [Abstract] Held-to-maturity Securities, Continuous Unrealized Loss Position [Abstract] Less Than 12 Months, Fair Value Held-to-maturity Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value Less Than 12 Months, Gross Unrealized Losses Held-to-maturity Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss 12 Months or Longer, Fair Value Held-to-maturity Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value 12 Months or Longer, Gross Unrealized Losses Held-to-maturity Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss Total Fair Value Held-to-maturity Securities, Continuous Unrealized Loss Position, Fair Value Total Gross Unrealized Losses Held-to-maturity Securities, Continuous Unrealized Loss Position, Accumulated Loss Number of Investment Securities in an Unrealized Loss Position Number of Investment Securities in Unrealized Loss Position This element represents the number of investment securities that were in an unrealized loss position as of the balance sheet date. Selected Business Segment Financial Information Schedule of Segment Reporting Information, by Segment [Table Text Block] Revenue Recognition Revenue From Contract With Customer [Text Block] Revenue From Contract With Customer [Text Block] Income Statement [Abstract] Interest Income Interest and Dividend Income, Operating [Abstract] Interest and Fees on Loans and Leases Interest and Fee Income for Loans and Leases The aggregate interest and fee income generated by: (1) loans the Entity has positive intent and ability to hold for the foreseeable future, or until maturity or payoff, including commercial and consumer loans, whether domestic or foreign, which may consist of: (a) industrial and agricultural; (b) real estate; and (c) real estate construction loans; (d) trade financing; (e) lease financing; (f) home equity lines-of-credit; (g) automobile and other vehicle loans; and (h) credit card and other revolving-type loans, (2) loans and leases held-for-sale which may include mortgage loans, direct financing, and sales-type leases, (3) amortization of deferred leasing fees and deferred lease origination costs, and (4) amortization of deferred loan origination fees and costs. Income on Investment Securities Interest and Dividend Income, Securities, by Classification [Abstract] Available-for-Sale Interest and Dividend Income, Securities, Operating, Available-for-sale Held-to-Maturity Interest Income, Securities, Operating, Held-to-maturity Deposits Interest Income, Deposits with Financial Institutions Funds Sold Interest Income, Federal Funds Sold Other Other Interest and Dividend Income Total Interest Income Interest and Dividend Income, Operating Interest Expense Interest Expense [Abstract] Deposits Interest Expense, Deposits Securities Sold Under Agreements to Repurchase Interest Expense, Securities Sold under Agreements to Repurchase Funds Purchased Interest Expense, Federal Funds Purchased Short-term Borrowings Interest Expense, Short-term Borrowings Other Debt Interest Expense, Long-term Debt Total Interest Expense Interest Expense Net Interest Income Interest Income (Expense), Net Provision for Credit Losses Provision for Loan and Lease Losses Net Interest Income After Provision for Credit Losses Interest Income (Expense), after Provision for Loan Loss Noninterest Income Noninterest Income [Abstract] Mortgage Banking Mortgage Banking Income The noninterest income derived from mortgage banking activities. Includes fees earned from servicing held in portfolio loans as well as loans sold in the secondary market, gains and losses on the sale of mortgage loans to investors, activities related to mortgage servicing rights, and gains and losses resulting from mortgage-related derivative financial instruments. Investment Securities Gains (Losses), Net Gain (Loss) on Sale of Securities, Net Bank-Owned Life Insurance Bank Owned Life Insurance Income Total Noninterest Income Noninterest Expense Noninterest Expense [Abstract] Salaries and Benefits Labor and Related Expense Net Occupancy Occupancy, Net Net Equipment Equipment Expense Data Processing Communications and Information Technology Professional Fees Professional Fees FDIC Insurance Federal Deposit Insurance Corporation Premium Expense Other Other Noninterest Expense Total Noninterest Expense Noninterest Expense Income Before Provision for Income Taxes Income (Loss) from Continuing Operations before Income Taxes, Noncontrolling Interest Provision for Income Taxes Income Tax Expense (Benefit) Net Income Basic Earnings Per Share (in dollars per share) Earnings Per Share, Basic Diluted Earnings Per Share (in dollars per share) Earnings Per Share, Diluted Dividends Declared Per Share (in dollars per share) Common Stock, Dividends, Per Share, Declared Basic Weighted Average Shares (in shares) Weighted Average Number of Shares Outstanding, Basic Diluted Weighted Average Shares (in shares) Weighted Average Number of Shares Outstanding, Diluted Reconciliation of Diluted Shares Weighted Average Number of Shares Outstanding Reconciliation [Abstract] Denominator for Basic Earnings Per Share (in shares) Dilutive Effect of Equity Based Awards (in shares) Incremental Common Shares Attributable to Dilutive Effect of Share-based Payment Arrangements Denominator for Diluted Earnings Per Share (in shares) Antidilutive Stock Options and Restricted Stock Outstanding (in shares) Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount Balance Sheet Offsetting Offsetting Assets and Liabilities [Text Block] Offsetting Assets and Liabilities [Text Block] Schedule of Financing Receivables Past Due [Table] Schedule of Financing Receivables Past Due [Table] Financing Receivables, Period Past Due [Axis] Financing Receivables, Period Past Due [Axis] Financing Receivables, Period Past Due [Domain] Financing Receivables, Period Past Due [Domain] 30 - 59 Days Past Due Financing Receivables, 30 to 59 Days Past Due [Member] 60 - 89 Days Past Due Financing Receivables, 60 to 89 Days Past Due [Member] Past Due 90 Days or More Financing Receivables, Equal to Greater than 90 Days Past Due [Member] Aging Analysis of Accruing and Non-Accruing Loans and Leases Financing Receivable, Recorded Investment, Past Due [Line Items] Days Past Due Financing Receivable, Recorded Investment, Past Due Non-Accrual Financing Receivable, Recorded Investment, Nonaccrual Status Total Past Due and Non-Accrual Financing Receivable, Recorded Investment Past Due and Nonaccrual Status Recorded investment in financing receivables that are past due and of nonaccrual status as of the balance sheet date. Current Financing Receivable, Recorded Investment, Current Total Loans and Leases Non-Accrual Loans and Leases that are Current Financing Receivable Recorded Investment Nonaccrual Status, Current Represents nonaccrual loans that are not past due 30 days or more; however, full payment of principal and interest is still not expected. Number of days non-accrual loans are not past due Financing Receivable Recorded Investment, Nonaccrual Status, Current, Number of Days Not Past Due Represents the number of days that the nonaccrual loans that are not past due. Qualitative and Quantitative Information, Transferor's Continuing Involvement [Table] Qualitative and Quantitative Information, Transferor's Continuing Involvement [Table] Representations and Warranties [Line Items] Qualitative and Quantitative Information, Transferor's Continuing Involvement [Line Items] Continuing Involvement with Transferred Financial Assets, Principal Amount Outstanding Continuing Involvement with Transferred Financial Assets, Principal Amount Outstanding Number of Mortgage Loans Repurchased Number of Mortgage Loans Repurchased Number of Mortgage Loans Repurchased Unpaid principal balance of repurchased mortgage loans Cash Flows Between Transferor and Transferee, Purchases of Previously Transferred Financial Assets Number of Mortgage Loans Repurchased, Pending Number of Mortgage Loans Repurchased, Pending Number of Mortgage Loans Repurchased, Pending Number of Mortgage Loans Repurchased due to Loan Servicing Activities Number of Mortgage Loans Repurchased due to Loan Servicing Activities Number of Mortgage Loans Repurchased due to Loan Servicing Activities Number of Mortgage Loans Repurchased due to Loan Servicing Activities, Pending Number of Mortgage Loans Repurchased due to Loan Servicing Activities, Pending Number of Mortgage Loans Repurchased due to Loan Servicing Activities, Pending Current Residential Mortgage Loans Serviced for Third Parties as Percentage of Total Current Residential Mortgage Loans Serviced for Third Parties as Percentage of Total Residential Mortgage Loans Serviced for Third Parties that were Current as a Percentage of Total Residential Mortgage Loans Serviced for Third Parties. Fair Value, by Balance Sheet Grouping [Table] Fair Value, by Balance Sheet Grouping [Table] Measurement Basis [Axis] Measurement Basis [Axis] Fair Value Measurement [Domain] Fair Value Measurement [Domain] Portion at Fair Value Measurement [Member] Portion at Fair Value Measurement [Member] Carrying Amount Reported Value Measurement [Member] Fair Value Estimate of Fair Value Measurement [Member] 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] Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] Financial Instruments - Assets Financial Instruments, Financial Assets, Balance Sheet Groupings [Abstract] Loans Loans Receivable, Fair Value Disclosure Financial Instruments - Liabilities Financial Instruments, Financial Liabilities, Balance Sheet Groupings [Abstract] Time Deposits Fair value, time deposits Fair value of time deposits that cannot be withdrawn before a set date without penalty or for which notice of withdrawal is required. Time deposits include, but are not limited to, certificates of deposits, individual retirement accounts and open accounts. Securities Sold Under Agreements to Repurchase Securities Loaned or Sold under Agreements to Repurchase, Fair Value Disclosure Other Debt Long Term Debt, Excluding Capital Lease Obligations, Fair Value The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. This element excludes the capital lease obligations. Credit commitments Other Commitments [Table Text Block] Interest Income from Investment Securities, Taxable Interest Income, Securities, Operating, Taxable Interest Income from Investment Securities, Non-Taxable Interest Income, Securities, Operating, Tax Exempt Total Interest Income from Investment Securities Interest Income, Operating Schedule of Sensitivity Analysis of Fair Value, Transferor's Interests in Transferred Financial Assets [Table] Schedule of Sensitivity Analysis of Fair Value, Transferor's Interests in Transferred Financial Assets [Table] Sensitivity analysis of fair value of mortgage servicing rights to changes in certain key assumptions Sensitivity Analysis of Fair Value of Interests Continued to be Held by Transferor, Servicing Assets or Liabilities, Impact of Adverse Change in Assumption [Line Items] Constant Prepayment Rate Sensitivity Analysis of Fair Value of Interests Continued to be Held by Transferor, Servicing Assets or Liabilities, Impact in Prepayment Speed [Abstract] -- None. No documentation exists for this element. -- Decrease in fair value from 25 basis points (“bps”) adverse change Sensitivity Analysis of Fair Value of Interests Continued to be Held by Transferor, Servicing Assets or Liabilities, Impact from 25 Basis Points Adverse Change in Prepayment Speed The hypothetical financial impact of 25 basis points' adverse change of prepayment speed on the fair value of transferor's interests in transferred financial assets (including any servicing assets or servicing liabilities) as of the balance sheet date. Decrease in fair value from 50 bps adverse change Sensitivity Analysis of Fair Value of Interests Continued to be Held by Transferor, Servicing Assets or Liabilities, Impact from 50 Basis Points Adverse Change in Prepayment Speed The hypothetical financial impact of 50 basis points' adverse change of prepayment speed on the fair value of transferor's interests in transferred financial assets (including any servicing assets or servicing liabilities) as of the balance sheet date. Discount Rate Sensitivity Analysis of Fair Value of Interests Continued to be Held by Transferor, Servicing Assets or Liabilities, Impact in Discount Rate [Abstract] -- None. No documentation exists for this element. -- Decrease in fair value from 25 bps adverse change Sensitivity Analysis of Fair Value of Interests Continued to be Held by Transferor, Servicing Assets or Liabilities, Impact from 25 Basis Points Adverse Change in Discount Rate The hypothetical financial impact of a 25 basis points adverse change of the discount rate on the fair value of transferor's interests in transferred financial assets (including any servicing assets or servicing liabilities) as of the balance sheet date. Decrease in fair value from 50 bps adverse change Sensitivity Analysis of Fair Value of Interests Continued to be Held by Transferor, Servicing Assets or Liabilities, Impact from 50 Basis Points Adverse Change in Discount Rate The hypothetical financial impact of a 50 basis points adverse change of the discount rate on the fair value of transferor's interests in transferred financial assets (including any servicing assets or servicing liabilities) as of the balance sheet date. Offsetting Assets and Liabilities [Table] Offsetting Assets and Liabilities [Table] Offsetting Assets and Liabilities [Table] Counterparty Name [Axis] Counterparty Name [Axis] Counterparty Name [Domain] Counterparty Name [Domain] Institutional Counterparties Institutional Counterparties [Member] Institutional Counterparties [Member] Private Institutions Private Institutions [Member] Private Institutions [Member] Government Entities Government Entities [Member] Government Entities [Member] Offsetting Assets and Liabilities [Line items] Offsetting Assets and Liabilities [Line Items] [Line Items] for Offsetting Assets and Liabilities [Table] Net liability positions, aggregate fair value Derivative, Net Liability Position, Aggregate Fair Value Derivative Liability, Fair Value of Collateral Derivative Liability, Fair Value of Collateral Securities Sold under Agreements to Repurchase, Fair Value of Collateral Securities Sold under Agreements to Repurchase, Fair Value of Collateral Assets: Offsetting Assets [Abstract] Offsetting Assets [Abstract] Gross Amounts of Recognized Assets Derivative Asset, Fair Value, Gross Asset Gross Amounts Offset in the Statements of Condition Derivative Asset, Fair Value, Gross Liability Net Amounts of Assets Presented in the Statements of Condition Derivative Asset, Fair Value, Amount Not Offset Against Collateral Netting Adjustments per Master Netting Arrangements Derivative Asset, Not Offset, Policy Election Deduction Gross Amounts Not Offset in the Statements of Condition - FV of collateral pledged Derivative, Collateral, Obligation to Return Securities Derivative Assets, Net Amount Derivative Asset, Fair Value, Amount Offset Against Collateral Liabilities: Offsetting Liabilities [Abstract] Offsetting Liabilities [Abstract] Gross Amounts of Recognized Liabilities Derivative Liability, Fair Value, Gross Liability Gross Amounts Offset in the Statements of Condition Derivative Liability, Fair Value, Gross Asset Net Amounts of Liabilities Presented in the Statements of Condition Derivative Liability, Fair Value, Amount Not Offset Against Collateral Derivative Liability, Netting Adjustments per Master Netting Arrangements Derivative Liability, Not Offset, Policy Election Deduction Derivative, Collateral, Right to Reclaim Securities Derivative, Collateral, Right to Reclaim Securities Derivative Liabilities, Net Amount Derivative Liability, Fair Value, Amount Offset Against Collateral Repurchase Agreements, Gross Amounts of Recognized Liabilities Repurchase Agreements, Gross Amounts Offset in the Statements of Condition Securities Sold under Agreements to Repurchase, Asset Repurchase Agreements, Net Amounts of Liabilities Presented in the Statements of Condition Securities Sold under Agreements to Repurchase Repurchase Agreements, Fair Value of Collateral Pledged Securities Sold under Agreements to Repurchase, Collateral, Right to Reclaim Securities Securities Sold under Agreements to Repurchase, Net Amount Offset Against Collateral Securities Sold under Agreements to Repurchase, Amount Offset Against Collateral Cash and Cash Equivalents Cash and Cash Equivalents Disclosure [Text Block] Pension Plans and Postretirement Benefit Plan Pension and Other Postretirement Benefits Disclosure [Text Block] Analysis of mortgage servicing rights accounted for under the fair value measurement method Schedule of Servicing Assets at Fair Value [Table Text Block] Analysis of mortgage servicing rights accounted for under the amortization method Servicing Asset at Amortized Cost [Table Text Block] Schedule of key data and assumptions used in estimating the fair value of mortgage servicing rights Schedule of Assumptions for Fair Value as of Balance Sheet Date of Assets or Liabilities that relate to Transferor's Continuing Involvement [Table Text Block] Schedule of sensitivity analysis of the fair value of mortgage servicing rights Schedule of Sensitivity Analysis of Fair Value, Transferor's Interests in Transferred Financial Assets [Table Text Block] Fair Value Inputs, Assets, Quantitative Information [Table] Fair Value Inputs, Assets, Quantitative Information [Table] Valuation Technique [Axis] Valuation Technique [Axis] Valuation Technique [Domain] Valuation Technique [Domain] Discounted Cash Flow Discounted Cash Flow Technique [Member] Discounted cash flow approach valuation technique used to measure fair value. Pricing Model Pricing Model Technique [Member] Pricing model approach valuation technique used to measure fair value. Level 3 Assets and Liabilities, Fair Value and Fair Value Unobservable Inputs Level 3 Assets and Liabilities, Fair Value and Fair Value Unobservable Inputs [Line Items] Level 3 Assets and Liabilities, Fair Value and Fair Value Unobservable Inputs [Line Items] Weighted Average Constant Prepayment Rate (as a percent) Fair Value Inputs, Prepayment Rate Weighted Average Discount Rate (as a percent) Fair Value Inputs, Discount Rate Weighted Average Closing Ratio (as a percent) Fair Value Inputs Closing Ratio Represents the percentage of loans currently in a lock position which management estimates will ultimately close. Weighted Average Credit Factor (as a percent) Fair Value Inputs, Entity Credit Risk Mortgage Servicing Rights, at Fair Value Mortgage Servicing Rights Fair Value Disclosure This element represents the assets reported on a recurring or nonrecurring basis on the balance sheet at period end at fair value. Interest Rate Derivative Instruments Not Designated as Hedging Instruments at Fair Value, Net Interest Rate Derivative Instruments Not Designated as Hedging Instruments at Fair Value, Net Gross Gains on Sales of Investment Securities Gain on Sale of Investment Securities, Gross The gross gain realized from the sale, exchange, redemption, or retirement of investment securities. Gross Losses on Sales of Investment Securities Loss on Sale of Investment Securities Gross The gross loss on the sale, exchange, redemption, or retirement of investment securities. Net Gains (Losses) on Sales of Investment Securities Statement of Cash Flows [Abstract] Operating Activities Net Cash Provided by (Used in) Operating Activities, Continuing Operations [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] Depreciation and Amortization Depreciation, Nonproduction Amortization of Deferred Loan and Lease Fees Amortization of Deferred Loan Origination Fees, Net Amortization and Accretion of Premiums/Discounts on Investment Securities, Net Accretion (Amortization) of Discounts and Premiums, Investments Share-Based Compensation Share-based Compensation Benefit Plan Contributions Pension and Other Postretirement Benefit Contributions Deferred Income Taxes Deferred Income Tax Expense (Benefit) Net Gains on Sales of Loans and Leases Gain (Loss) on Sale of Loans and Leases Net Losses (Gains) on Sales of Investment Securities Gain (Loss) on Investments Proceeds from Sales of Loans Held for Sale Proceeds from Sale of Loans Held-for-sale Originations of Loans Held for Sale Payments for Origination and Purchases of Loans Held-for-sale Net Tax Benefit from Share-Based Compensation Employee Service Share-based Compensation, Tax Benefit from Compensation Expense Net Change in Other Assets and Other Liabilities Increase (Decrease) in Other Operating Assets and Liabilities, Net Net Cash Provided by Operating Activities Net Cash Provided by (Used in) Operating Activities, Continuing Operations Investing Activities Net Cash Provided by (Used in) Investing Activities, Continuing Operations [Abstract] Investment Securities Available-for-Sale: Available-for-sale Securities [Abstract] Proceeds from Sales, Prepayments and Maturities Proceeds from Maturities, Prepayments and Calls of Available-for-sale Securities Purchases Payments to Acquire Available-for-sale Securities Investment Securities Held-to-Maturity: Proceeds from Sale and Maturity of Held-to-maturity Securities [Abstract] Proceeds from Prepayments and Maturities Proceeds from Maturities, Prepayments and Calls of Held-to-maturity Securities Purchases Payments to Acquire Held-to-maturity Securities Net Change in Loans and Leases Payments for (Proceeds from) Loans and Leases Proceeds from Sales of Loans Proceeds from Sale of Loans and Leases Held-for-investment Premises and Equipment, Net Payments for (Proceeds from) Productive Assets Net Cash Provided by (Used in) Investing Activities Net Cash Provided by (Used in) Investing Activities, Continuing Operations Financing Activities Net Cash Provided by (Used in) Financing Activities, Continuing Operations [Abstract] Net Change in Deposits Increase (Decrease) in Deposits Net Change in Short-Term Borrowings Proceeds from (Repayments of) Short-term Debt Repayments of Long-Term Debt Repayments of Long-term Debt Proceeds from Issuance of Common Stock Proceeds from Issuance of Common Stock Repurchase of Common Stock Payments for Repurchase of Common Stock Cash Dividends Paid Payments of Ordinary Dividends, Common Stock Net Cash Provided by Financing Activities Net Cash Provided by (Used in) Financing Activities, Continuing Operations Net Change in Cash and Cash Equivalents Net Cash Provided by (Used in) Continuing Operations Cash and Cash Equivalents at End of Period Cash and Cash Equivalents, at Carrying Value Cash and Cash Equivalents at Beginning of Period Supplemental Information Supplemental Cash Flow Information [Abstract] Cash Paid for Interest Interest Paid Cash Paid for Income Taxes Income Taxes Paid Non-Cash Investing Activities: Cash Flow, Noncash Investing and Financing Activities Disclosure [Abstract] Transfer from Loans to Foreclosed Real Estate Real Estate Owned, Transfer from Real Estate Owned Transfers from Loans to Loans Held for Sale Transfer of Portfolio Loans and Leases to Held-for-sale Statement of Stockholders' Equity [Abstract] Statement, Equity Components [Axis] Equity Components [Axis] Equity Component [Domain] Equity Component [Domain] Common Stock Common Stock [Member] Capital Surplus Additional Paid-in Capital [Member] Accumulated Other Comprehensive Income (Loss) AOCI Attributable to Parent [Member] Retained Earnings Retained Earnings [Member] Treasury Stock Treasury Stock [Member] Increase (decrease) in shareholders' equity Increase (Decrease) in Stockholders' Equity [Roll Forward] Balance at Beginning of Period Stockholders' Equity Attributable to Parent Beginning Balance (in shares) Other Comprehensive Loss Reclassification of the Income Tax Effect of the Tax Reform from AOCI to RE Reclassification of the Income Tax Effect of the Tax Reform from AOCI to RE Reclassification of the Income Tax Effect of the Tax Cuts and Job Act from AOCI to Retained Earning Share-Based Compensation Stock Issued During Period, Value, Share-based Compensation, Net of Forfeitures Common Stock Issued under Purchase and Equity Compensation Plans and Related Tax Benefits Stock Issued During Period, Value, Purchase and Equity Compensation Plans Value of stock issued during the period as a result of purchase and equity compensation plans. Common Stock Issued under Purchase and Equity Compensation Plans and Related Tax Benefits (in shares) Stock Issued During Period, Shares, Purchase and Equity Compensation Plans Number of shares issued during the period as a result of purchase and equity compensation plans. Common Stock Repurchased Treasury Stock, Value, Acquired, Cost Method Common Stock Repurchased (in shares) Treasury Stock, Shares, Acquired Cash Dividends Declared (per share) Dividends, Common Stock, Cash Balance at End of Period Ending Balance (in shares) Other Comprehensive Income (Loss), Before Tax: Other Comprehensive Income (Loss), before Tax, Portion Attributable to Parent [Abstract] Net Unrealized Gains (Losses) Arising During the Period Other Comprehensive Income (Loss), Unrealized Holding Gain (Loss) on Securities Arising During Period, before Tax Amortization of Unrealized Holding (Gains) Losses on HTM Securities Other Comprehensive Income Reclassification Adjustment for Amortization of Held To Maturity holding Gainsbefore Tax Other Comprehensive Income Reclassification Adjustment for Amortization of holding Gains for Securities Held-To-Maturity before Tax Net Unrealized Gains (Losses) on Investment Securities Other Comprehensive Income, Unrealized Losses on Investment Securities, Before Tax Gross appreciation or the gross loss in value of the total of unsold available-for-sale securities, net of pre-tax reclassification adjustments for gains or losses realized upon the sale of securities and amortization of Available-for-Sale holding gains moved to Held-to-Maturity. Amortization of Net Actuarial Losses (Gains) Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI, Pension and Other Postretirement Benefit Plans, for Net Gain (Loss), before Tax Amortization of Prior Service Credit Other Comprehensive (Income) Loss, Amortization Adjustment from AOCI, Pension and Other Postretirement Benefit Plans, for Net Prior Service Cost (Credit), before Tax Defined Benefit Plans, Net Other Comprehensive (Income) Loss, Pension and Other Postretirement Benefit Plans, Adjustment, before Tax, Portion Attributable to Parent Other Comprehensive Income (Loss) Other Comprehensive Income (Loss), before Tax, Portion Attributable to Parent Other Comprehensive Income (Loss), Tax Effect: Other Comprehensive Income (Loss), Tax, Portion Attributable to Parent, Parenthetical Disclosures [Abstract] Net Unrealized Gains (Losses) Arising During the Period Other Comprehensive Income (Loss), Unrealized Holding Gain (Loss) on Securities Arising During Period, Tax Amortization of Unrealized Holding (Gains) Losses on HTM Securities The tax effect of other comprehensive income reclassification for amortization of holding gains/losses on HTM Securities, tax effect. The tax effect of other comprehensive income reclassification for amortization of holding gains/losses on HTM Securities. Net Unrealized Gains (Losses) on Investment Securities Tax effect on Unrealized gain/loss on Investment Securities Tax effect on unrealized gain/loss on available-for-sale securities, net or tax effect of reclassification adjustments for gains or losses realized upon the sale of securities and amortization of available-for-sale holdings gains moved to Held-to_maturity. Amortization of Net Actuarial Losses (Gains) Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI, Pension and Other Postretirement Benefit Plans, for Net Gain (Loss), Tax Amortization of Prior Service Credit Other Comprehensive (Income) Loss, Amortization Adjustment from AOCI, Pension and Other Postretirement Benefit Plans, for Net Prior Service Cost (Credit), Tax Defined Benefit Plans, Net Other Comprehensive (Income) Loss, Pension and Other Postretirement Benefit Plans, Tax, Portion Attributable to Parent Other Comprehensive Income (Loss) Other Comprehensive Income (Loss), Tax, Portion Attributable to Parent Other Comprehensive Income (Loss), Net of Tax: Net Unrealized Gains (Losses) Arising During the Period Other Comprehensive Income (Loss), Unrealized Holding Gain (Loss) on Securities Arising During Period, Net of Tax Amortization of Unrealized Holding (Gains) Losses on HTM Securities Other Comprehensive Income Reclassification Adjustment for Amortization of Gains on Held To Maturity Securities after Tax Other Comprehensive Income Reclassification Adjustment for Amortization of Holding Gains on Held To Maturity Securities after Tax Net Unrealized Gains (Losses) on Investment Securities Amortization of Net Actuarial Losses (Gains) Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI, Pension and Other Postretirement Benefit Plans, for Net Gain (Loss), Net of Tax Amortization of Prior Service Credit Other Comprehensive (Income) Loss, Amortization Adjustment from AOCI, Pension and Other Postretirement Benefit Plans, for Net Prior Service Cost (Credit), Net of Tax Defined Benefit Plans, Net Federal Home Loan Bank Stock Federal Home Loan Bank Stock Federal Reserve Bank Stock Federal Reserve Bank Stock Total Federal Home Loan Bank Stock and Federal Reserve Bank Stock Receive Fixed / Pay Variable Swap Receive Fixed or Pay Variable Swap [Member] Represents the receive fixed or pay variable interest rate swap agreements. Pay Fixed / Receive Variable Swap Pay Fixed or Receive Variable Swap [Member] Represents the pay fixed or receive variable interest rate swap agreements. Derivative [Line Items] Derivative [Line Items] Notional Amount Derivative, Notional Amount Fair Value Derivative, Fair Value, Net Schedule of Servicing Assets at Fair Value [Table] Schedule of Servicing Assets at Fair Value [Table] Servicing Assets at Fair Value [Line Items] Servicing Assets at Fair Value [Line Items] Mortgage servicing rights accounted for under the fair value measurement method [Rollforward] Servicing Asset at Fair Value, Amount [Roll Forward] Balance at Beginning of Period Servicing Asset at Fair Value, Amount Due to Payoffs Servicing Asset at Fair Value, Other Changes in Fair Value Total Changes in Fair Value of Mortgage Servicing Rights Servicing Asset at Fair Value, Period Increase (Decrease) Balance at End of Period Affordable Housing Tax Credit Investments, Unfunded Commitment [Abstract] Affordable Housing Tax Credit Investments, Unfunded Commitment [Abstract] Affordable Housing Tax Credit Investments, Unfunded Commitment [Abstract] 2018 Qualified Affordable Housing Project Investments, Commitment Payments, Remainder of Fiscal Year Qualified Affordable Housing Project Investments, Commitment Payments, Remainder of Fiscal Year 2019 Qualified Affordable Housing Project Investments, Commitment Payments, Year Two Qualified Affordable Housing Project Investments, Commitment Payments, Year Two 2020 Qualified Affordable Housing Project Investments, Commitment Payments, Year Three Qualified Affordable Housing Project Investments, Commitment Payments, Year Three 2021 Qualified Affordable Housing Project Investments, Commitment Payments, Year Four Qualified Affordable Housing Project Investments, Commitment Payments, Year Four 2022 Qualified Affordable Housing Project Investments, Commitment Payments, Year Five Qualified Affordable Housing Project Investments, Commitment Payments, Year Five Thereafter Qualified Affordable Housing Project Investments, Commitment Payments, After Year Five Qualified Affordable Housing Project Investments, Commitment Payments, After Year Five Total Unfunded Commitments Investments in Affordable Housing Projects [Abstract] Investments in Affordable Housing Projects [Abstract] Effective Yield Method Effective Yield Method [Abstract] Effective Yield Method [Abstract] Tax credits and other tax benefits recognized Affordable Housing Tax Credits and Other Tax Benefits, Amount Amortization Expense in Provision for Income Taxes Amortization Method Qualified Affordable Housing Project Investments, Amortization Proportional Amortization Method Proportional Amortization Method [Abstract] Proportional Amortization Method [Abstract] Tax credits and other tax benefits recognized Affordable Housing Tax Credits, Proportional Amortization Method Affordable Housing Tax Credits, Proportional Amortization Method Amortization Expense in Provision for Income Taxes Proportional Amortization Method, Qualified Affordable Housing Project Investments, Amortization Proportional Amortization Method, Qualified Affordable Housing Project Investments, Amortization Net affordable housing tax credit investments and related unfunded commitments Amortization Method Qualified Affordable Housing Project Investments Write down from impairment of LIHTC Investments Affordable Housing Project Investment, Write-down, Amount Low income housing investment partnerships basis adjustments, provision income tax expense Tax Cuts and Jobs Act of 2017, Incomplete Accounting, Change in Tax Rate, Low Income Housing Investment Basis Adjustment, Provisional Income Tax (Expense) Benefit Tax Cuts and Jobs Act of 2017, Incomplete Accounting, Change in Tax Rate, Low Income Housing Investment Basis Adjustment, Provisional Income Tax (Expense) Benefit Schedule of the notional amount and fair value of the derivative financial instruments Schedule of Derivative Instruments [Table Text Block] Derivative financial instruments, their fair values, and balance sheet location Schedule of Derivative Instruments in Statement of Financial Position, Fair Value [Table Text Block] Derivative financial instruments and the amount and location of the net gains or losses recognized in the statements of income Derivative Instruments, Gain (Loss) [Table Text Block] Schedule of Servicing Assets at Amortized Value [Table] Servicing Asset at Amortized Cost [Table] Servicing Assets at Amortized Value by Types of Financial Instruments [Axis] Servicing Asset at Amortized Cost [Line Items] Servicing Asset at Amortized Cost [Line Items] Mortgage Servicing Rights Accounted for Under the Amortization Method {Rollforward) Servicing Asset at Amortized Cost, Balance [Roll Forward] Balance at Beginning of Period Servicing Rights that Resulted From Asset Transfers Servicing Asset at Amortized Cost, Additions Amortization Servicing Asset at Amortized Cost, Amortization Balance at End of Period Valuation Allowance for Impairment of Mortgage Servicing Rights Accounted for under the Amortization Method [Roll Forward] Valuation Allowance for Impairment of Recognized Servicing Assets [Roll Forward] Fair Value of Mortgage Servicing Rights Accounted for Under the Amortization Method Fair Value of Mortgage Servicing Rights Accounted for under Amortization Method [Abstract] Represents the fair value of mortgage servicing rights at the beginning and ending of the period accounted for under the amortization method. Beginning of Period Servicing Asset at Amortized Cost, Fair Value End of Period Residential mortgage loans serviced for third parties Residential Mortgage Loans Serviced for Third Parties This element represents the amount of residential mortgage loans serviced for third parties. Servicing income, including late and ancillary fees Contractually Specified Servicing Fees, Late Fees, and Ancillary Fees Earned in Exchange for Servicing Financial Assets Schedule of components of net periodic benefit cost Schedule of Net Benefit Costs [Table Text Block] Document and Entity Information [Abstract] Document and Entity Information Entity Registrant Name Entity Registrant Name Entity Central Index Key Entity Central Index Key Document Type Document Type Document Period End Date Document Period End Date Amendment Flag Amendment Flag Current Fiscal Year End Date Current Fiscal Year End Date Entity Current Reporting Status Entity Current Reporting Status Entity Filer Category Entity Filer Category Entity Common Stock, Shares Outstanding Entity Common Stock, Shares Outstanding Document Fiscal Year Focus Document Fiscal Year Focus Document Fiscal Period Focus Document Fiscal Period Focus Schedule of Financing Receivable, Allowance for Credit Losses [Table] Schedule of Financing Receivable, Allowance for Credit Losses [Table] Allowance for Loan and Lease Losses Financing Receivable, Allowance for Credit Losses [Line Items] Allowance for Loan and Lease Losses: Financing Receivable, Allowance for Credit Losses [Roll Forward] Balance at Beginning of Period Financing Receivable, Allowance for Credit Losses Loans and Leases Charged-Off Financing Receivable, Allowance for Credit Losses, Write-downs Recoveries on Loans and Leases Previously Charged-Off Allowance for Loan and Lease Loss, Recovery of Bad Debts Net Loans and Leases Recovered (Charged-Off) Allowance for Loan and Lease Losses Write-offs, Net Provision for Credit Losses Balance at End of Period Allowance for Loan and Lease Losses: Financing Receivable, Allowance for Credit Loss, Additional Information [Abstract] Individually Evaluated for Impairment Financing Receivable, Allowance for Credit Losses, Individually Evaluated for Impairment Collectively Evaluated for Impairment Financing Receivable, Allowance for Credit Losses, Collectively Evaluated for Impairment Total Recorded Investment in Loans and Leases: Loans and Leases Receivable Investment [Abstract] -- None. No documentation exists for this element. -- Individually Evaluated for Impairment Financing Receivable, Individually Evaluated for Impairment Collectively Evaluated for Impairment Financing Receivable, Collectively Evaluated for Impairment Accumulated Other Comprehensive Income (Loss) [Table] Accumulated Other Comprehensive Income (Loss) [Table] Debt Security Category [Axis] Debt Security Category [Axis] Other than Temporary Impairment, Credit Losses Recognized in Earnings, Categories of Investments [Domain] Other than Temporary Impairment, Credit Losses Recognized in Earnings, Categories of Investments [Domain] Available-for-sale Securities Available-for-sale Securities [Member] Held-to-maturity Securities Held-to-maturity Securities [Member] Equity Components [Axis] Unrealized Gains and Losses on Net Investment Securities Accumulated Net Investment Gain (Loss) Attributable to Parent [Member] Defined Benefit Plans Accumulated Defined Benefit Plans Adjustment Attributable to Parent [Member] Accumulated Other Comprehensive Income (Loss) [Line Items] Accumulated Other Comprehensive Income (Loss) [Line Items] Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward] AOCI Attributable to Parent, Net of Tax [Roll Forward] Other Comprehensive Income (Loss) Before Reclassifications OCI, before Reclassifications, Net of Tax, Attributable to Parent Amounts Reclassified from Accumulated Other Comprehensive Income (Loss) Reclassification from AOCI, Current Period, Net of Tax, Attributable to Parent Fair Value, Measurements, Recurring Fair Value, Measurements, Recurring [Member] Quoted Prices in Active Markets for Identical Assets or Liabilities (Level 1) Debt Securities Issued by the U.S. Treasury and Government Agencies US Treasury and Government Agencies [Member] This category includes investments in debt securities issued by the United States Department of the Treasury and U.S. Government Agencies. Such securities may include treasury bills (short-term maturities - one year or less), treasury notes (intermediate term maturities - two to ten years), treasury bonds (long-term maturities - ten to thirty years), and debt securities issued by the Government National Mortgage Association (Ginnie Mae). Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] Assets: Assets, Fair Value Disclosure [Abstract] Loans Held for Sale Loans Receivable Held-for-sale, Net, Not Part of Disposal Group Mortgage Servicing Rights Other Assets Other Assets, Fair Value Disclosure Derivatives Derivative Asset Total Assets Measured at Fair Value on a Recurring Basis Assets, Fair Value Disclosure Liabilites: Liabilities, Fair Value Disclosure [Abstract] Derivatives Derivative Liability Total Liabilities Measured at Fair Value on a Recurring Basis Financial and Nonfinancial Liabilities, Fair Value Disclosure Investment Income [Table] Investment Income [Table] Investment Type [Axis] Investment Type [Axis] Investments [Domain] Investments [Domain] Visa Class B Restricted Securities Visa Class B Restricted Securities [Member] Visa Class B Restricted Securities [Member] Visa Class A Unrestricted Securities Visa Class A Unrestricted Securities [Member] Visa Class A Unrestricted Securities [Member] Net Investment Income [Line Items] Net Investment Income [Line Items] Conversion Ratio to Class A shares Conversion Ratio of Convertible Securities Conversion Ratio of Convertible Securities Gain on Sale of Investment Securities Equity securities remaining, shares Equity Securities, Shares Equity Securities, Shares Visa Conversion Rate Swap Agreement Visa Conversion Rate Swap Agreement [Member] Visa Class B to Class A Conversion Rate Swap Agreement [Member] Credit Commitments [Table] Other Commitments [Table] Credit Commitments [Axis] Other Commitments [Axis] Types of Credit Commitments [Domain] Other Commitments [Domain] Unfunded Commitments to Extend Credit Commitments to Extend Credit [Member] Standby Letters of Credit Standby Letters of Credit [Member] Commercial Letters of Credit Letter of Credit [Member] Credit Commitments [Line Items] Other Commitments [Line Items] Credit Commitments Fair Value Disclosure, Off-balance Sheet Risks, Face Amount, Liability Interest-Bearing Deposits in Other Banks Interest-bearing Deposits in Banks and Other Financial Institutions Funds Sold Funds Sold Amount represents balances maintained with the Federal Reserve Bank. Cash and Due From Banks Due from Banks Total Cash and Cash Equivalents Debt Securities Issued by the U.S. Treasury and Government Agencies Debt Securities Issued by States and Political Subdivisions Debt Securities Issued by Corporations Available-for-Sale: Available-for-sale Securities, Fair Value to Amortized Cost Basis [Abstract] Available-for-Sale: Amortized Cost Available-for-Sale: Gross Unrealized Gains Available-for-sale Securities, Accumulated Gross Unrealized Gain, before Tax Available-for-Sale: Gross Unrealized Losses Available-for-sale Securities, Accumulated Gross Unrealized Loss, before Tax Available-for-Sale Held-to-maturity Securities [Abstract] Held-to-maturity Securities [Abstract] Held-to-Maturity: Amortized Cost Held-to-maturity Securities Held-to-Maturity: Gross Unrealized Gains Held-to-maturity Securities, Accumulated Unrecognized Holding Gain Held-to-Maturity: Gross Unrealized Losses Held-to-maturity Securities, Accumulated Unrecognized Holding Loss Fair Value of Assets and Liabilities Fair Value Disclosures [Text Block] Reclassification Out of Accumulated Other Comprehensive Income [Table] Reclassification out of Accumulated Other Comprehensive Income [Table] Amortization of Unrealized Gains(Losses) of Investment Securities Transferred from AFS to HTM Amortization of Unrealized Gains(Losses) of Investment Securities Transferred from AFS to HTM [Member] Amortization of Unrealized Gains(Losses) of Investment Securities Transferred from AFS to HTM [Member] Amortization of Defined Benefit Pension Items Prior Service Credit Accumulated Defined Benefit Plans Adjustment, Net Prior Service Attributable to Parent [Member] Net Actuarial Losses Accumulated Defined Benefit Plans Adjustment, Net Gain (Loss) Attributable to Parent [Member] Reclassification Out of Accumulated Other Comprehensive Income [Axis] Reclassification out of Accumulated Other Comprehensive Income [Axis] Reclassification Out of Accumulated Other Comprehensive Income [Domain] Reclassification out of Accumulated Other Comprehensive Income [Domain] Reclassification out of Accumulated Other Comprehensive Income Reclassification out of Accumulated Other Comprehensive Income [Member] Reclassification Out of Accumulated Other Comprehensive Income [Line Items] Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items] Interest Income Investment Income, Interest Salaries and Benefits Tax Benefit (Expense) Schedule of Segment Reporting Information, by Segment [Table] Schedule of Segment Reporting Information, by Segment [Table] Statement, Business Segments [Axis] Segments [Axis] Segment [Domain] Segments [Domain] Retail Banking Retail Banking [Member] This element represents selected financial information of the retail banking business segment. Commercial Banking Commercial Banking [Member] This element represents selected financial information of the commercial banking business segment. Investment Services and Private Banking Investment Services [Member] This element represents selected financial information of the investment services business segment. Treasury and Other Treasury and Other [Member] This element represents selected financial information of the treasury business segment. Business segment financial information Segment Reporting Information [Line Items] Federal and State effective tax rate used for segment reporting Federal and State Effective Tax Rate Used for Segment Reporting The combined Federal and State Effective Tax Rate Used for Segment Reporting purposes. Number of branch locations through which products and services are delivered to customers Number of Branch Locations through which Products and Services Delivered to Customers The number of branch locations through which products and services are delivered to customers. Number of ATM's through which products and services are delivered to customers Number of A T M s through which Products and Services Delivered to Customers The number of ATMs through which products and services are delivered to customers. Net Interest Income Net Interest Income After Provision for Credit Losses Noninterest Expense Income Before Provision for Income Taxes Provision for Income Taxes Total Assets Assets Schedule of Impaired Financing Receivable [Table] Schedule of Impaired Financing Receivable [Table] Impaired Loans Information: Financing Receivable, Impaired [Line Items] Impaired Financing Receivable, with No Related Allowance, Recorded Investment Impaired Financing Receivable, with No Related Allowance, Recorded Investment Impaired Financing Receivable, with No Related Allowance, Unpaid Principal Balance Impaired Financing Receivable, with No Related Allowance, Unpaid Principal Balance Impaired Financing Receivable, with Related Allowance, Recorded Investment Impaired Financing Receivable, with Related Allowance, Recorded Investment Impaired Financing Receivable, with Related Allowance, Unpaid Principal Balance Impaired Financing Receivable, with Related Allowance, Unpaid Principal Balance Related Allowance for Loan Losses Impaired Financing Receivable, Related Allowance Recorded Investment Impaired Financing Receivable, Recorded Investment Unpaid Principal Balance Impaired Financing Receivable, Unpaid Principal Balance Impaired Financing Receivable, with No Related Allowance, Average Recorded Investment Impaired Financing Receivable, with No Related Allowance, Average Recorded Investment Impaired Financing Receivable, with No Related Allowance, Interest Income Recognized, Accrual Method Impaired Financing Receivable, with No Related Allowance, Interest Income, Accrual Method Impaired Financing Receivable, with Related Allowance, Average Recorded Investment Impaired Financing Receivable, with Related Allowance, Average Recorded Investment Impaired Financing Receivable, with Related Allowance, Interest Income Recognized, Accrual Method Impaired Financing Receivable, with Related Allowance, Interest Income, Accrual Method Impaired Loans Average Recorded Investment Impaired Financing Receivable, Average Recorded Investment Impaired Loans Interest Income Recognized Impaired Financing Receivable, Interest Income, Accrual Method Land Loan Land Loan [Member] A loan for land. Maximum Maximum [Member] Recorded Investment Financing Receivable, Modifications, Recorded Investment Available Commitments to Lend Additional Funds on Loans Modified as TDR Available commitments under Revolving Credit Lines, Modified as TDR Available commitments under revolving credit lines that have been modified as TDRs. Period of Time Loan Being Fully Amortized Period of Time Loan Being Fully Amortized Period of Time Loan Being Fully Amortized Extending Balloon Payments Extending Balloon Payments Period of modification related to loans that have been modified in a troubled debt restructuring where the balloon payment is extended. Number of Contracts Financing Receivable, Modifications, Number of Contracts Recorded Investment (as of period end) Financing Receivable, Modifications, Post-Modification Recorded Investment Increase in Allowance (as of period end) Financing Receivable Modifications, Impact on Allowance Represents the modification impact on allowance at the end of the period. Schedule of Accounts, Notes, Loans and Financing Receivable [Table] Schedule of Accounts, Notes, Loans and Financing Receivable [Table] Loan and lease portfolio Accounts, Notes, Loans and Financing Receivable [Line Items] Loans and Leases Net Gains Related to Sales of Residential Mortgage Loans Gain (Loss) on Sale of Mortgage Loans Provisional income tax expense Tax Cuts and Jobs Act of 2017, Incomplete Accounting, Change in Tax Rate, Deferred Tax Liability, Provisional Income Tax (Expense) Benefit Tax Cuts and Jobs Act of 2017, Incomplete Accounting, Change in Tax Rate, Deferred Tax Liability, Provisional Income Tax (Expense) Benefit Accumulated Other Comprehensive Income (Loss) Comprehensive Income (Loss) Note [Text Block] Basis of Presentation Basis of Accounting, Policy [Policy Text Block] Use of Estimates in the Preparation of Financial Statements Use of Estimates, Policy [Policy Text Block] Variable Interest Entities Consolidation, Variable Interest Entity, Policy [Policy Text Block] Accounting Standards Adopted in the Current Year or Pending Adoption New Accounting Pronouncements, Policy [Policy Text Block] Balances of assets and liabilities measured at fair value on a recurring basis Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis [Table Text Block] Changes in Level 3 assets and liabilities measured at fair value on a recurring basis Fair Value Assets and Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Table Text Block] Tabular disclosure of the fair value measurement of assets and liabilities using significant unobservable inputs (Level 3), a reconciliation of the beginning and ending balances, separately presenting changes during the period attributable to the following: (1) total gains or losses for the period (realized and unrealized), segregating those gains or losses included in earnings (or changes in net assets) and gains or losses recognized in other comprehensive income, and a description of where those gains or losses included in earnings (or changes in net assets) are reported in the statement of income (or activities); (2) purchases, sales, issuances, and settlements (each type disclosed separately); and (3) transfers in and transfers out of Level 3 (for example, transfers due to changes in the observability of significant inputs), by class of asset and liability. Summary of the significant unobservable inputs Fair Value Inputs, Assets, Quantitative Information [Table Text Block] Assets and liabilities measured at fair value on a nonrecurring basis Fair Value Measurements, Nonrecurring [Table Text Block] Schedule of difference between the aggregate fair value and the aggregate unpaid principal balance of the Company's residential mortgage loans held for sale Fair Value, Option, Quantitative Disclosures [Table Text Block] Schedule of carrying amount, fair value, and fair value hierarchy of financial instruments Fair Value, by Balance Sheet Grouping [Table Text Block] Derivative Instruments, Gain (Loss) by Hedging Relationship, by Income Statement Location, by Derivative Instrument Risk [Table] Derivative Instruments, Gain (Loss) [Table] Income Statement Location [Axis] Income Statement Location [Axis] Income Statement Location [Domain] Income Statement Location [Domain] Mortgage Banking Income Mortgage Banking Income [Member] Details pertaining to noninterest income derived from mortgage banking activities. Other Noninterest Income Other Income [Member] Derivative Instruments, Gain (Loss) Derivative Instruments, Gain (Loss) [Line Items] Net gains (losses) recognized in the statements of income Derivative, Gain (Loss) on Derivative, Net Assets Assets [Abstract] Interest-Bearing Deposits in Other Banks Funds Sold Investment Securities Marketable Securities [Abstract] Held-to-Maturity (Fair Value of $3,711,149 and $3,894,121) Allowance for Loan and Lease Losses Loans and Leases Receivable, Allowance Net Loans and Leases Loans and Leases Receivable, Net Amount Total Earning Assets Earning Assets Aggregate total of all income-earning assets owned by the entity. Premises and Equipment, Net Property, Plant and Equipment, Net Accrued Interest Receivable Interest Receivable Foreclosed Real Estate Real Estate Acquired Through Foreclosure Mortgage Servicing Rights Mortgage Servicing Rights: The total of mortgage servicing rights, both those carried at fair value and those carried at amortized cost. Mortgage servicing rights consist of an asset representing the present value of estimated future revenues from contractually specified servicing fees, late charges, and other ancillary revenues, in excess of future costs related to servicing arrangements. Rights may be obtained via (1) acquisition or assumption of a servicing obligation that does not relate to financial assets of the servicer or its consolidated affiliates; or (2) by originating loans and then transferring the loans in a transaction that meets the requirements for sale accounting. Goodwill Goodwill Bank-Owned Life Insurance Bank Owned Life Insurance Other Assets Other Assets Total Assets Liabilities Liabilities [Abstract] Deposits Deposits [Abstract] Noninterest-Bearing Demand Noninterest-bearing Deposit Liabilities Interest-Bearing Demand Interest Bearing Demand Deposit Liabilities The amount of money in accounts that bear interest and that the depositor is entitled to withdraw at any time without prior notice. Includes both domestic and foreign depositors. Savings Deposits, Savings Deposits Time Time Deposits Total Deposits Deposits Securities Sold Under Agreements to Repurchase Other Debt Long-term Debt and Capital Lease Obligations Retirement Benefits Payable Pension and Other Postretirement Defined Benefit Plans, Liabilities Accrued Interest Payable Interest Payable Taxes Payable and Deferred Taxes Taxes Payable and Deferred Taxes Obligations related to taxes payable and deferred taxes. Taxes payable includes the carrying value as of the balance sheet date of obligations incurred and payable for statutory income, sales, excise, and other taxes. Deferred taxes includes the cumulative amount for all deferred tax liabilities as of the balance sheet date arising from temporary differences between accounting income in accordance with generally accepted accounting principles and tax-basis income that will result in future taxable income exceeding future accounting income. Other Liabilities Other Liabilities Total Liabilities Liabilities Shareholders’ Equity Stockholders' Equity Attributable to Parent [Abstract] Common Stock ($.01 par value; authorized 500,000,000 shares; issued / outstanding: March 31, 2018 - 58,051,646 / 42,314,414 and December 31, 2017 - 57,959,074 / 42,401,443) Common Stock, Value, Issued Capital Surplus Additional Paid in Capital, Common Stock Accumulated Other Comprehensive Loss Accumulated Other Comprehensive Income (Loss), Net of Tax Treasury Stock, at Cost (Shares: March 31, 2018 - 15,737,232 and December 31, 2017 - 15,557,631) Treasury Stock, Value Total Shareholders’ Equity Total Liabilities and Shareholders’ Equity Liabilities and Equity