Loans Receivable and Allowance for Loan Losses (Narrative) (Details)	12 Months Ended
Dec. 31, 2022 USD ($) loan	Dec. 31, 2021 USD ($)	Dec. 31, 2020 USD ($)
Accounts, Notes, Loans and Financing Receivable [Line Items]
Certain Loans and Debt Securities Acquired in Transfer, Allowance for Credit Losses Due to Subsequent Impairment	$ 0
Financing Receivable, Modifications, Post-Modification Recorded Investment	0
Financing Receivable, Troubled Debt Restructuring	0
Financing Receivables, Impaired, Troubled Debt Restructuring, Write-down	0
Loans acquired with credit deterioration	15,410,000
Real Estate Acquired Through Foreclosure	$ 346,000	$ 1,742,000
Number Of Properties Under Foreclosure Proceedings \| loan	4
Annual Loan Review threshold, amount	$ 1,500,000
Loans and Leases Receivable, Gross	1,474,424,000	1,356,040,000
Proceeds from Sale of Mortgage Loans Held-for-sale	845,000	8,616,000
Allowance for Loan and Lease Losses, Adjustments, Other	2,400,000	1,500,000
Allowance for Loan and Lease Losses, Period Increase (Decrease)	557,000	3,292,000
Loans and Leases Receivable, Impaired, Interest Lost on Nonaccrual Loans	182,000	35,000
Allowance for Loan and Lease Losses, Real Estate	16,999,000	16,442,000	$ 13,150,000
Servicing Asset at Amortized Cost	60,000,000.0	65,400,000
Outstanding Balance	8,368,000	12,862,000
Hospitality Lodging Industry [Member] \| Loans Receivable [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivables, Impaired, Troubled Debt Restructuring, Write-down	0	0
Residential Real Estate Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Mortgage Loans in Process of Foreclosure, Amount	223,000
Loans and Leases Receivable, Gross	298,813,000	273,040,000
Proceeds from Sale of Mortgage Loans Held-for-sale	848,000	8,793,000
Gross Realized Gains on Loans	3,000	177,000
Gross Realized Losses on Loans	0	0
Residential Real Estate Loans [Member] \| Hospitality Lodging Industry [Member] \| Loans Receivable [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases Receivable, Gross	$ 113,000,000.0
Concentration Risk, Percentage	7.70%
Commercial Real Estate Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Number Of Properties Under Foreclosure Proceedings \| loan	1
Loans and Leases Receivable, Gross	$ 651,544,000	628,724,000
Commercial Real Estate Loans [Member] \| Commercial Rentals [Member] \| Loans Receivable [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases Receivable, Gross	$ 141,900,000
Concentration Risk, Percentage	9.60%
PPP Loan [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases Receivable, Gross	$ 121,000	15,209,000
Fee income	0	2,900,000
UpState New York Bancorp, Inc. [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Assets, Fair Value Adjustment	6,937,000
Outstanding Balance	15,410,000
COVID [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for Loan and Lease Losses, Period Increase (Decrease)	445,000	$ 1,400,000
Economic Conditions [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for Loan and Lease Losses, Period Increase (Decrease)	$ 2,300,000

Annual Loan Review Threshold, Amount

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Gross Realized Gains on Loans

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Gross Realized Losses on Loans

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Number Of Properties Under Foreclosure Proceedings

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Amount of other addition (reduction) in allowance reserve for credit loss.

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Amount of increase (decrease) of allowance reserve for credit loss.

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The reserve to cover probable credit losses related to specifically identified fixed maturity real estate loans as well as probable credit losses inherent in the remainder of that loan portfolio.

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Amount of addition (reduction) to the amount at which an asset could be incurred (settled) in a current transaction between willing parties.

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The undiscounted sum of all amounts, including amounts deemed principal, interest, fees, penalties, and other under the loan, owed to the investor at the reporting date, whether or not currently due and whether or not any such amounts have been written or charged off by the investor. This relates to loans accounted for as debt securities, with evidence of deterioration of credit quality since origination that were acquired by completion of a transfer for which it is probable, at acquisition, that the investor will be unable to collect all contractually required payments receivable.

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The recorded balance, net of any applicable reductions (for example, unamortized accretable yield and allowance for loan losses). This relates to loans not accounted for debt securities with evidence of deterioration of credit quality since origination that were acquired by completion of a transfer for which it is probable, at acquisition, that the investor will be unable to collect all contractually required payments receivable.

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For loans and debt securities, 1) for which at acquisition it was probable that the investor would be unable to collect all contractually required payments receivable, and 2) for which it is further probable that the investor will not be able to collect all cash flows expected at acquisition (plus any additional cash flows expected due to changes in estimate after acquisition), the allowance for credit losses recorded to reflect the impairment since acquisition.

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For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

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Amount, after troubled debt restructuring, of modified financing receivable.

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Amount of financing receivable modified as troubled debt restructuring.

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Reflects the amount of the write-down related to a troubled debt restructuring.

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Interest and fee income related to commercial loans including industrial and agricultural, real estate (commercial and residential, construction and development), trade financing, and lease financing.

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Amount before allowance of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans and leases covered under loss sharing agreements.

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Reflects the amount of additional interest income that would have been recorded if impaired or nonperforming loans were instead current, in compliance with their original terms, and outstanding throughout the reporting period or since origination (if held for part of the period).

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Recorded investment of consumer mortgage loan receivables secured by residential real estate properties for which formal foreclosure proceedings are in process.

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The cash inflow from sales of loans that are secured with real estate mortgages and are held with the intention to resell in the near future.

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Carrying amount as of the balance sheet date of land and buildings obtained through foreclosure proceedings or defeasance in full or partial satisfaction of a debt arrangement.

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