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Change in Unrealized Gain (Loss) on Hedged Item in Fair Value Hedge All Executive Categories All Executive Categories [Member] Off-Balance-Sheet, Credit Loss, Liability [Roll Forward] Off-Balance-Sheet, Credit Loss, Liability [Roll Forward] Total loans and leases Financing Receivable, before Allowance for Credit Loss, Fee and Loan in Process Class of Financing Receivable [Axis] Class of Financing Receivable [Axis] Pension Adjustments Service Cost Pension Adjustments Service Cost [Member] Net (gain) loss on securities transactions Marketable Security, Realized Gain (Loss) Schedule of Federal Home Loan Bank Advances, by Branch of FHLB Bank [Table] Federal Home Loan Bank, Advance, Branch of FHLBank [Table] Less: average unvested stock-based compensation awards (in shares) Incremental Common Shares Attributable to Participating Nonvested Shares with Non-forfeitable Dividend Rights Total Debt Securities, Available-for-Sale, Maturity, Allocated and Single Maturity Date, Amortized Cost 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Tompkins, Cayuga, Cortland and Schuyler Counties, New York [Member] Segment and Related Information Segment Reporting [Text Block] Securities Investment in Debt and Equity Securities and Other Trading Assets [Text Block] Proceeds from maturities, calls and principal paydowns of available-for-sale debt securities Proceeds from Maturities, Prepayments and Calls of Debt Securities, Available-for-Sale Minimum Minimum [Member] Cash dividends Payments of Ordinary Dividends, Common Stock Less than 12 Months Debt Securities, Held-to-Maturity, Continuous Unrealized Loss Position, Less than 12 Months, Fair Value Expiration Date Trading Arrangement Expiration Date Commercial and industrial other Commercial and industrial other Other Financing Receivable [Member] Other Financing Receivable [Member] LIABILITIES Liabilities [Abstract] Reclassification Adjustment out of Accumulated Other Comprehensive Income on Derivatives [Line Items] Reclassification Adjustment out of Accumulated Other 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Adjustments Service Cost [Member] Other income Noninterest Income, Other Operating Income Proceeds from sale/redemptions of Federal Home Loan Bank stock Proceeds from Sale of Federal Home Loan Bank Stock Common stock, authorized (in shares) Common Stock, Shares Authorized Accumulated Other Comprehensive Income (Loss) [Line Items] Accumulated Other Comprehensive Income (Loss) [Line Items] Schedule of Held-to-maturity Securities [Line Items] Schedule of Held-to-Maturity Securities [Line Items] Due after ten years Debt Securities, Available-for-Sale, Fair Value, Maturity, Allocated and Single Maturity Date, after Year 10 Total Financing Receivable, Individually Evaluated for Credit Loss Exercise Price Award Exercise Price Total held-to-maturity debt securities Debt Securities, Held-to-Maturity, Excluding Accrued Interest, after Allowance for Credit Loss Restricted stock activity Stock Issued During Period, Value, Restricted Stock Award, Net of Forfeitures INVESTING ACTIVITIES Cash 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Awards Close in Time to MNPI Disclosures, Table Awards Close in Time to MNPI Disclosures [Table Text Block] Equity Component [Domain] Equity Component [Domain] PEO Actually Paid Compensation Amount PEO Actually Paid Compensation Amount Realized gains or losses on called available-for-sale debt securities Debt Securities, Available For Sale, Called, Realized Gain (Loss) Debt Securities, Available For Sale, Called, Realized Gain (Loss) Loans/leases, net Loans Receivable, Fair Value Disclosure Number of wholly owned subsidiaries Number Of Wholly-Owned Banking Subsidiary Number Of Wholly-Owned Banking Subsidiary Fair Value Debt Securities, Available-for-Sale, Fair Value, Fiscal Year Maturity [Abstract] Adoption Date Trading Arrangement Adoption Date Cash dividends Dividends, Common Stock, Cash Equity securities, at fair value Equity securities, at fair value Equity Securities, FV-NI, Current ASSETS Assets [Abstract] Title Trading Arrangement, Individual Title Forgone Recovery due to Disqualification of Tax Benefits, Amount Forgone Recovery due to Disqualification of Tax Benefits, Amount Leases Finance Leases Finance Leases Portfolio Segment [Member] Payment Delay Payment Deferral [Member] Accounting Policies [Abstract] Accounting Policies [Abstract] Restatement does not require Recovery Restatement Does Not Require Recovery [Text Block] Less: income attributable to unvested stock-based compensation awards Income Allocated To Unvested Restricted Stock Awards This element represents the income allocated to unvested restricted stock awards. 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available-for-sale debt securities AOCI, Accumulated Gain (Loss), Debt Securities, Available-for-Sale, Parent [Member] Erroneously Awarded Compensation Recovery Erroneously Awarded Compensation Recovery [Table] Net retirement plan actuarial loss Accumulated Defined Benefit Plans Adjustment, Net Gain (Loss) Attributable to Parent [Member] Increase (Decrease) in Stockholders' Equity [Roll Forward] Increase (Decrease) in Stockholders' Equity [Roll Forward] Proceeds from sale of other real estate owned Payments for (Proceeds from) Previous Acquisition Change in net unrealized gain (loss) during the period OCI, Debt Securities, Available-for-Sale, Unrealized Holding Gain (Loss), before Adjustment, after Tax Award Timing Disclosures [Line Items] Schedule of Carrying Amount and Fair Value of Financial Instruments Fair Value, by Balance Sheet Grouping [Table Text Block] Financing Receivable, Past Due [Line Items] Financing Receivable, Past Due [Line Items] Diluted Earnings Per Share (in dollars per share) Diluted EPS (in dollars per share) Earnings Per Share, Diluted Accumulated Other Comprehensive Income (Loss) [Table] Accumulated Other Comprehensive Income (Loss) [Table] Entity Current Reporting Status Entity Current Reporting Status Net Cash Provided by (Used in) Financing Activities Cash Provided by (Used in) Financing Activity, Including Discontinued Operation Internal Credit Assessment [Axis] Internal Credit Assessment [Axis] Total Shareholder Return Amount Total Shareholder Return Amount Less: Provision for credit loss expense Provision for credit loss expense Financing Receivable, Credit Loss, Expense (Reversal) Liabilities Liabilities, Fair Value Disclosure [Abstract] Amortization of intangible assets Intangible Asset, Finite-Lived, Amortization Expense Stockholders' Equity Note [Abstract] Stockholders' Equity Note [Abstract] Three years before current fiscal year Financing Receivable, Excluding Accrued Interest, Year Four, Originated, Three Years before Current Fiscal Year Adjustments to reconcile net income to cash provided by (used in) operating activities: Adjustment to Reconcile Net Income to Cash Provided by (Used in) Operating Activity [Abstract] 12 Months or Longer Debt Securities, Held-to-Maturity, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss Reclassification adjustment Reclassification from AOCI, Current Period, Tax FINANCING ACTIVITIES Cash Provided by (Used in) Financing Activity, Including Discontinued Operation [Abstract] Bank premises and equipment, net Property, Plant, and Equipment, after Accumulated Depreciation, Depletion, and Amortization Loans Other Interest and Dividend Income Financial Instruments [Domain] Financial Instruments [Domain] Financial Instruments [Domain] Federal funds purchased and securities sold under agreements to repurchase Fed funds purchased and securities sold under agreements to repurchase Federal Funds Purchased and Securities Sold under Agreements to Repurchase Financial Assets: Financial Instruments, Financial Assets, Balance Sheet Groupings [Abstract] Four years before current fiscal year Financing Receivable, Excluding Accrued Interest, Year Five, Originated, Four Years before Current Fiscal Year Derivative assets Derivative assets, fair value Derivative Asset Common stock repurchased and returned to unissued status Stock Repurchased During Period, Value Equity Awards Adjustments, Footnote Equity Awards Adjustments, Footnote [Text Block] Underlying Securities Award Underlying Securities Amount Fair Value Estimate of Fair Value Measurement [Member] U.S. Government sponsored entities Mortgage-Backed Security, Issued by US Government-Sponsored Enterprise [Member] Fair Values Derivatives, Balance Sheet Location, by Derivative Contract Type [Table] Fair Values Derivatives, Balance Sheet Location, by Derivative Contract Type [Table] Increase in accrued interest payable Increase (Decrease) in Interest Payable, Net Term Extension and Interest Rate Reduction Extended Maturity and Interest Rate Reduction [Member] Segment Reporting [Table] Segment Reporting [Table] Total Amortized cost basis Financing Receivable, Excluding Accrued Interest, Modified in Period, Amount Federal funds purchased and securities sold under agreements to repurchase Interest Expense, Federal Funds Purchased and Securities Sold under Agreements to Repurchase Home equity Home Equity Loan [Member] Guarantees [Abstract] Guarantees [Abstract] Liabilities for off-balance sheet credit exposures at beginning of period Liabilities for off-balance sheet credit exposures at end of period Off-Balance-Sheet, Credit Loss, Liability Transfer of loans to other real estate owned Transfer Of Loans To Other Real Estate Owned Value of loans transferred to other real estate owned in noncash transactions during the reporting period. All Trading Arrangements All Trading Arrangements [Member] Less than 12 Months Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, Less than 12 Months Other Performance Measure, Amount Other Performance Measure, Amount Award Timing MNPI Considered Award Timing MNPI Considered [Flag] Current Fiscal Year End Date Current Fiscal Year End Date Increase in other borrowings Proceeds from Issuance of Debt Non-PEO NEO Average Total Compensation Amount Non-PEO NEO Average Total Compensation Amount Collateral [Axis] Collateral Held [Axis] Common stock repurchased and returned to unissued status (in shares) Stock Repurchased During Period, Shares Change in Fair Value as of Vesting Date of Prior Year Equity Awards Vested in Covered Year Change in Fair Value as of Vesting Date of Prior Year Equity Awards Vested in Covered Year [Member] Cash dividends (in dollars per share) Common Stock, Dividends, Per Share, Declared Entity File Number Entity File Number Rule 10b5-1 Arrangement Adopted Rule 10b5-1 Arrangement Adopted [Flag] Schedule of Amortized Cost and Estimated Fair Value of Debt Securities by Contractual Maturity Investments Classified by Contractual Maturity Date [Table Text Block] Proceeds from redemption of corporate owned life insurance Proceeds from Life Insurance Policy Revolving Loans Amortized Cost Basis Financing Receivable, Excluding Accrued Interest, Revolving Recovery of Erroneously Awarded Compensation Disclosure [Line Items] Schedule of Originated and Acquired Credit Losses by Portfolio Segment Financing Receivable, Allowance for Credit Loss [Table Text Block] Common stock, issued (in shares) Common Stock, Shares, Issued Measure: Measure [Axis] Interest bearing: Interest-Bearing Deposit Liabilities [Abstract] Treasury stock at cost (in shares) Treasury Stock, Common, Shares 12 Months or Longer Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss Other Comprehensive Income (Loss) Comprehensive Income (Loss) Note [Text Block] Equity Components [Axis] Equity Components [Axis] Cash paid during the year for - Taxes Income Tax Paid, after Refund Received Banking Banking Segment [Member] Banking Segment Due after one year through five years Debt Securities, Held-to-Maturity, Amortized Cost Excluding Accrued Interest, after Allowance for Credit Loss, Maturity, Allocated and Single Maturity Date, after Year One through Five Entity Interactive Data Current Entity Interactive Data Current Salaries and wages Salary and Wage, NonOfficer, Excluding Cost of Good and Service Sold NONINTEREST EXPENSE Noninterest Expense [Abstract] Compensation Actually Paid vs. Other Measure Compensation Actually Paid vs. Other Measure [Text Block] Amount of Gain or (Loss) Recognized in Income on Derivative Derivative Instruments Not Designated as Hedging Instruments, Gain (Loss), Net Due after one year through five years Debt Securities, Available-for-Sale, Amortized Cost, Maturity, Allocated and Single Maturity Date, after Year One Through Five Entity Small Business Entity Small Business Total comprehensive income Comprehensive Income (Loss), Net of Tax, Attributable to Parent Termination Date Trading Arrangement Termination Date Fair Value, Recurring and Nonrecurring [Table] Fair Value, Recurring and Nonrecurring [Table] Compensation Actually Paid vs. Total Shareholder Return Compensation Actually Paid vs. Total Shareholder Return [Text Block] Net Interest Income Interest Income (Expense), Operating MNPI Disclosure Timed for Compensation Value MNPI Disclosure Timed for Compensation Value [Flag] Obligations of U.S. Government sponsored entities Obligations of U.S. Government sponsored entities US Government-sponsored Enterprises Debt Securities [Member] Document Type Document Type Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] Fair Value as of Grant Date Award Grant Date Fair Value Schedule of Debt Securities, Available for Sale with Unrealized Losses Debt Securities, Available-for-Sale, Unrealized Loss Position, Fair Value [Table Text Block] Pay vs Performance Disclosure, Table Pay vs Performance [Table Text Block] Arrangement Duration Trading Arrangement Duration Statement of Stockholders' Equity [Abstract] Statement of Stockholders' Equity [Abstract] Local Phone Number Local Phone Number Less: unearned income and deferred costs and fees Financing Receivable, Unamortized Loan Cost (Fee) and Purchase Premium (Discount) Consolidation Items [Axis] Consolidation Items [Axis] Entity Address, Postal Zip Code Entity Address, Postal Zip Code Entity Registrant Name Entity Registrant Name (Increase)/decrease in loans originated for sale Increase (Decrease) In Loan, Originated For Sale Increase (Decrease) In Loan, Originated For Sale Counties North Of New York City Counties North Of New York City [Member] Putnam Country, Dutchess Country and Westchester, New York [Member] Less than 12 Months Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss Income before income tax expense Total before tax Income (Loss) from Continuing Operations before Income Taxes, Noncontrolling Interest Insider Trading Policies and Procedures Not Adopted Insider Trading Policies and Procedures Not Adopted [Text Block] Other borrowings Interest Expense, Other Available-for-sale debt securities: Net of Tax OCI, Debt Securities, Available-for-Sale, Gain (Loss), after Adjustment and Tax [Abstract] Changed Peer Group, Footnote Changed Peer Group, Footnote [Text Block] Reclassification out of Accumulated Other Comprehensive Income [Axis] Reclassification out of Accumulated Other Comprehensive Income [Axis] Forgone Recovery due to Expense of Enforcement, Amount Forgone Recovery due to Expense of Enforcement, Amount Executive Category: Executive Category [Axis] Loan Restructuring Modification [Axis] Loan Restructuring Modification [Axis] Other comprehensive income (loss), net unrealized loss Other Comprehensive Income (Loss), Tax Total Debt Securities, Available-for-Sale, Maturity, Allocated and Single Maturity Date, Fair Value Schedule 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] All Award Types Award Type [Domain] Non-PEO NEO Average Compensation Actually Paid Amount Non-PEO NEO Average Compensation Actually Paid Amount Fair value of derivatives in a net liability position Derivative, Net Liability Position, Aggregate Fair Value Fair Value Option, Disclosures [Table] Fair Value Option, Disclosures [Table] Fair Value Measurements Fair Value Disclosures [Text Block] Net gain on sale of loans originated for sale Gain (Loss) on Sales of Loans, Net (Level 3) (Level 3) Fair Value, Inputs, Level 3 [Member] U.S. Government agencies US Government Agencies Debt Securities [Member] Supplemental Information: Supplemental Cash Flow Information [Abstract] PEO Name PEO Name Geographical [Axis] Geographical [Axis] Non-Accrual Financial Assets, Non-Accrual [Member] Financial Assets, Non-Accrual Financial Liabilities: Financial Instruments, Financial Liabilities, Balance Sheet Groupings [Abstract] 12 Months or Longer Debt Securities, Held-to-Maturity, Continuous Unrealized Loss Position, 12 Months or Longer, Fair Value Home equity Home Equity Line of Credit [Member] Stock Price or TSR Estimation Method Stock Price or TSR Estimation Method [Text Block] 30-59 Days Financial Asset, 30 to 59 Days Past Due [Member] Entity Tax Identification Number Entity Tax Identification Number Derivative Instruments and Hedging Activities Disclosures [Table] Derivative Instruments and Hedging Activities Disclosures [Table] Cash and noninterest bearing balances due from banks Cash and Due from Banks Schedule of Age Analysis of Past Due Loans Financing Receivable, Past Due [Table Text Block] Current Loans Financial Asset, Not Past Due [Member] Fair Value Debt Securities, Held-to-Maturity, Unrealized Loss Position, Fair Value [Abstract] NONINTEREST INCOME Noninterest Income [Abstract] Cash and cash equivalents, beginning of the period Total Cash and Cash Equivalents at End of Period Cash, Cash Equivalent, Restricted Cash, and Restricted Cash Equivalent, Continuing Operation Treasury stock activity and issued Stock Issued During Period, Value, Treasury Stock Reissued Entity Incorporation, State or Country Code Entity Incorporation, State or Country Code Earnings from corporate owned life insurance Bank Owned Life Insurance Income Aggregate Erroneous Compensation Not Yet Determined Aggregate Erroneous Compensation Not Yet Determined [Text Block] Schedule of Accumulated Other Comprehensive Income (Loss) Reclassification out of Accumulated Other Comprehensive Income [Table Text Block] Material Terms of Trading Arrangement Material Terms of Trading Arrangement [Text Block] Non-NEOs Non-NEOs [Member] Vesting Date Fair Value of Equity Awards Granted and Vested in Covered Year Vesting Date Fair Value of Equity Awards Granted and Vested in Covered Year [Member] Business Organization, Consolidation and Presentation of Financial Statements Disclosure [Text Block] Total Comprehensive Income Comprehensive Income (Loss), Net of Tax, Including Portion Attributable to Noncontrolling Interest Measurement Frequency [Domain] Measurement Frequency [Domain] Net (decrease) increase in time deposits Increase (Decrease) in Time Deposits Stock-based compensation expense Share-Based Payment Arrangement, Noncash Expense INTEREST EXPENSE Interest Expense, Operating and Nonoperating [Abstract] Fair Value Debt Securities, Held-to-Maturity, Fair Value, Maturity [Abstract] Net increase in loans Payments for (Proceeds from) Loans and Leases Other deposits Interest Expense, Other Domestic Deposits Due after five years through ten years Debt Securities, Available-for-Sale, Amortized Cost, Maturity, Allocated and Single Maturity Date, after Year 5 Through 10 Schedule of Derivative Instruments in Statement of Financial Position, Fair Value Schedule of Derivative Instruments in Statement of Financial Position, Fair Value [Table Text Block] Basic Earnings Per Share (in dollars per share) Basic EPS (in dollars per share) Earnings Per Share, Basic Repurchase of common stock Payments for Repurchase of Common Stock Net (loss) gain on securities transactions Net gain (loss) on securities transactions Debt Securities, Available-for-sale, Realized Gain (Loss) On Transactions Debt Securities, Available-for-sale, Realized Gain (Loss) On Transactions Statistical Measurement [Axis] Statistical Measurement [Axis] Proceeds from sale of loans originated for sale Proceeds from Sale, Loan, Originated For Sale Proceeds from Sale, Loan, Originated For Sale Insider Trading Arrangements [Line Items] Schedule of Derivative Instruments in Statement of Income Derivative Instruments, Gain (Loss) [Table Text Block] Award Type Award Type [Axis] Interest Rate Products Interest Rate Contract [Member] Named Executive Officers, Footnote Named Executive Officers, Footnote [Text Block] Real Estate Real Estate [Member] Retained earnings Retained Earnings (Accumulated Deficit) Consumer Consumer Portfolio Segment [Member] Corporate owned life insurance Bank Owned Life Insurance Aggregate Change in Present Value of Accumulated Benefit for All Pension Plans Reported in Summary Compensation Table Aggregate Change in Present Value of Accumulated Benefit for All Pension Plans Reported in Summary Compensation Table [Member] Awards Close in Time to MNPI Disclosures Awards Close in Time to MNPI Disclosures [Table] Common Stock Common Stock [Member] Other borrowings Other borrowings Other Borrowings Available for sale debt securities, fair value Debt Securities, Available-for-Sale Fair Value Measurement [Domain] Fair Value Measurement [Domain] Reclassification out of Accumulated Other Comprehensive Income [Table] Reclassification out of Accumulated Other Comprehensive Income [Table] Other employee benefits Other Postretirement Benefits Cost (Reversal of Cost) Compensation Actually Paid vs. Company Selected Measure Compensation Actually Paid vs. Company Selected Measure [Text Block] Four years before current fiscal year Financing Receivable, Excluding Accrued Interest, Year Five, Originated, Four Years before Current Fiscal Year, Writeoff Cover [Abstract] Cover [Abstract] Agriculture Agriculture Loans [Member] Agriculture Loans [Member] Derivative Contract [Domain] Derivative Contract [Domain] One year before current fiscal year Financing Receivable, Excluding Accrued Interest, Year Two, Originated, Fiscal Year before Current Fiscal Year, Writeoff Other deposits Other Deposits, Fair Value Disclosure Represents fair value of other deposits. Equity Awards Adjustments Equity Awards Adjustments [Member] Total Past Due Financial Asset, Past Due [Member] Realized gains or losses on sales of available-for-sale debt securities Debt Securities, Available-for-Sale, Realized Gain (Loss) Total Liabilities and Equity Liabilities and Equity Other comprehensive (loss) income, net of tax: Other comprehensive income, net of tax: Employee Stock Option Share-Based Payment Arrangement, Option [Member] Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] Reclassification adjustment Reclassification from Accumulated Other Comprehensive Income, Current Period, before Tax Segments [Axis] Segments [Axis] Additional 402(v) Disclosure Additional 402(v) Disclosure [Text Block] Asset Class [Axis] Asset Class [Axis] Revolving Loans Converted to Term Financing Receivable, Excluding Accrued Interest, Revolving, Converted to Term Loan, Writeoff Pass Pass [Member] Schedule of Fair Value Hedging Instruments, Statements of Financial Performance and Financial Position, Location Schedule of Fair Value Hedging Instruments, Statements of Financial Performance and Financial Position, Location [Table Text Block] Schedule of Loans and Leases Schedule of Accounts, Notes, Loans and Financing Receivable [Table Text Block] Tabular List, Table Tabular List [Table Text Block] Amortization of net retirement plan prior service cost Other Comprehensive (Income) Loss, Defined Benefit Plan, Prior Service Cost (Credit), Reclassification Adjustment from AOCI, after Tax Net proceeds from exercise of stock options Proceeds From (Outlays For) Stock Options Exercised Proceeds From (Outlays For) Stock Options Exercised Cumulative Amount of Fair Value Hedging Adjustment Included in the Carrying Amount of the Hedged Assets/(Liabilities) Hedged Asset, Fair Value Hedge, Cumulative Increase (Decrease) Name Awards Close in Time to MNPI Disclosures, Individual Name EQUITY Equity, Including Portion Attributable to Noncontrolling Interest [Abstract] Checking, savings and money market Checking, Savings And Money Market Amount of interest bearing deposits with no stated maturity, which may include passbook and statement savings accounts and money-market deposit accounts (MMDAs). Year-end Fair Value of Equity Awards Granted in Covered Year that are Outstanding and Unvested Year-end Fair Value of Equity Awards Granted in Covered Year that are Outstanding and Unvested [Member] Commercial and Industrial Commercial & Industrial Commercial and Industrial Commercial And Industrial Portfolio Segment [Member] Commercial And Industrial Portfolio Segment [Member] Financing Receivable Portfolio Segment [Axis] Financing Receivable Portfolio Segment [Axis] Derivatives, Fair Value [Line Items] Derivatives, Fair Value [Line Items] Business Assets Business Assets [Member] Business Assets [Member] Adjustment to Compensation: Adjustment to Compensation [Axis] Transfer of loans to other assets Transfer Of Loans To Other Assets Transfer Of Loans To Other Assets Reclassification adjustment Amounts reclassified from accumulated other comprehensive (loss) income Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax Hedging Designation [Domain] Hedging Designation [Domain] Rule 10b5-1 Arrangement Terminated Rule 10b5-1 Arrangement Terminated [Flag] Aggregate Erroneous Compensation Amount Aggregate Erroneous Compensation Amount Cash paid during the year for - Interest Interest Paid, Excluding Capitalized Interest, Operating Activity Statement of Cash Flows [Abstract] Statement of Cash Flows [Abstract] Federal Home Loan Bank, advances, branch of FHLB bank, amount of advances Federal Home Loan Bank, Advance, Branch of FHLBank, Amount Hedging Designation [Axis] Hedging Designation [Axis] 60-89 Days Financial Asset, 60 to 89 Days Past Due [Member] Aggregate Available Trading Arrangement, Securities Aggregate Available Amount Name Measure Name Individually evaluated loans Impaired Loans Refers to fair value amount of collateral dependent impaired loans as of balance sheet date. Pay vs Performance Disclosure [Line Items] Fair Value Hierarchy and NAV [Domain] Fair Value Hierarchy and NAV [Domain] Fair Value Hierarchy and NAV [Domain] Pay vs Performance Disclosure Pay vs Performance Disclosure [Table] Additional Paid-in Capital Additional Paid-in Capital [Member] Entity Filer Category Entity Filer Category Total Debt Securities, Available-for-Sale, Unrealized Loss Position Accrued interest receivable Interest Receivable Name Trading Arrangement, Individual Name Cash and Cash Equivalents Cash and Cash Equivalent Net increase in demand, money market, and savings deposits Increase (Decrease) in Other Deposits Basis of Presentation Basis of Accounting [Text Block] Company Selected Measure Amount Company Selected Measure Amount Financial Asset, Aging [Axis] Financial Asset, Aging [Axis] Derivatives not designated as hedging instruments Not Designated as Hedging Instrument [Member] Investments, Debt and Equity Securities [Abstract] Investments, Debt and Equity Securities [Abstract] Deposits: Deposits [Abstract] Number of banking offices Nature Of Operations, Number Of Banking Offices Nature Of Operations, Number of Banking Offices Entity Address, Address Line Two Entity Address, Address Line Two Directors deferred compensation plan (in shares) Shares Issued, Shares, Share-Based Payment Arrangement, after Forfeiture Allowance for Loan and Lease Losses [Roll Forward] Allowance for Loan and Lease Losses [Roll Forward] Schedule of Accounts, Notes, Loans and Financing Receivable [Table] Accounts and Financing Receivables [Table] Net income Net income Net Income (Loss), Including Portion Attributable to Noncontrolling Interest Derivatives not designated as hedging instruments Derivative liabilities, fair value Derivative Liability Non-PEO NEO Non-PEO NEO [Member] Entity Address, Address Line One Entity Address, Address Line One Right-of-use assets obtained in exchange for new lease liabilities Right-of-Use Asset Obtained in Exchange for Operating Lease Liability U.S. corporate debt securities Debt Security, Corporate, US [Member] Income Tax Expense Income tax expense Income tax expense Income Tax Expense (Benefit) Total Noninterest Expenses Noninterest expense Noninterest Expense Total amounts of income and expense line items presented in the statement of financial performance in which the effects of fair value or cash flow hedges are recorded Gain (Loss) on Fair Value Hedges Recognized in Earnings Award Timing Method Award Timing Method [Text Block] Available-for-sale securities Available-for-Sale Securities, Continuous Unrealized Loss Position, Qualitative Disclosure [Abstract] Consolidation Consolidation, Policy [Policy Text Block] Net Increase in Cash and Cash Equivalents Cash, Cash Equivalent, Restricted Cash, and Restricted Cash Equivalent, Period Increase (Decrease), Including Exchange Rate Effect and Discontinued Operation Total Loans Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss, Writeoff Forgone Recovery, Explanation of Impracticability Forgone Recovery, Explanation of Impracticability [Text Block] Hedged Asset, Statement Of Financial Position Extensible Enumeration, Not Disclosed Flag Hedged Asset, Statement Of Financial Position Extensible Enumeration, Not Disclosed Flag Hedged Asset, Statement Of Financial Position Extensible Enumeration, Not Disclosed Flag Derivative liabilities, notional amount Derivative Liability, Notional Amount Net Income Net Income Net income available to common shareholders Net Income (Loss) Attributable to Parent Erroneous Compensation Analysis Erroneous Compensation Analysis [Text Block] Loan Restructuring Modification [Domain] Loan Restructuring Modification [Domain] Statement [Table] Statement [Table] Proceeds from sale of bank premises and equipment Proceeds from Sale of Property, Plant, and Equipment Financing Receivable, Past Due [Table] Financing Receivable, Past Due [Table] Restatement Determination Date: Restatement Determination Date [Axis] Schedule of Tax Effect Allocated to each Component of Other Comprehensive Income (Loss) Schedule of Accumulated Other Comprehensive Income (Loss) [Table Text Block] One year before current fiscal year Financing Receivable, Excluding Accrued Interest, Year Two, Originated, Fiscal Year before Current Fiscal Year Schedule of Nonaccrual Loans Financing Receivable, Nonaccrual [Table Text Block] Derivative Instruments and Hedging Activities Disclosures [Line Items] Derivative Instruments and Hedging Activities Disclosures [Line Items] Recoveries Financing Receivable, Allowance for Credit Loss, Recovery Collateral posted from counterparty Collateral Already Posted, Aggregate Fair Value Pension Benefits Adjustments, Footnote Pension Benefits Adjustments, Footnote [Text Block] Derivative Instruments and Hedging Activities Disclosure [Abstract]