Allowance for Loan Losses and Credit Quality Allocation of Investment in Loans, by Impairment Methodology (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Financing Receivable, Allowance for Credit Loss [Line Items]
Individually evaluated for impairment	$ 4,621	$ 5,241
Collectively evaluated for impairment	766,548	665,003
Total	771,169	670,244
Residential loans
Financing Receivable, Allowance for Credit Loss [Line Items]
Individually evaluated for impairment	1,782	1,515
Collectively evaluated for impairment	181,384	190,610
Total	183,166	192,125
Construction real estate
Financing Receivable, Allowance for Credit Loss [Line Items]
Individually evaluated for impairment	210	223
Collectively evaluated for impairment	57,207	69,394
Total	57,417	69,617
Commercial real estate
Financing Receivable, Allowance for Credit Loss [Line Items]
Individually evaluated for impairment	2,422	3,204
Collectively evaluated for impairment	318,205	286,679
Total	320,627	289,883
Commercial loans
Financing Receivable, Allowance for Credit Loss [Line Items]
Individually evaluated for impairment	207	299
Collectively evaluated for impairment	108,654	47,400
Total	108,861	47,699
Consumer
Financing Receivable, Allowance for Credit Loss [Line Items]
Individually evaluated for impairment	0	0
Collectively evaluated for impairment	2,601	3,562
Total	2,601	3,562
Municipal
Financing Receivable, Allowance for Credit Loss [Line Items]
Individually evaluated for impairment	0	0
Collectively evaluated for impairment	98,497	67,358
Total	$ 98,497	$ 67,358

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The balance of financing receivables that were collectively evaluated for impairment.

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The balance of financing receivables that were individually evaluated for impairment.

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Amount, before allowance for credit loss, of financing receivable.

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