Loans Receivable and Allowance for Loan Losses - Balance in Allowance for Loan Losses and Recorded Investment (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Allowance for loan losses:
Collectively evaluated for impairment	$ 2,712	$ 2,642
Total ending allowance balance	2,712	2,642	$ 2,548
Loans:
Individually evaluated for impairment	1,313	3,110
Collectively evaluated for impairment	1,586,183	1,574,246
Total ending loan balance	1,587,496	1,577,356
Residential Mortgage
Allowance for loan losses:
Collectively evaluated for impairment	1,741	1,797
Total ending allowance balance	1,741	1,797	1,721
Loans:
Individually evaluated for impairment	1,224	2,962
Collectively evaluated for impairment	1,543,125	1,537,292
Total ending loan balance	1,544,349	1,540,254
Construction, Commercial and Other Mortgage Loans
Allowance for loan losses:
Collectively evaluated for impairment	511	443
Total ending allowance balance	511	443	539
Loans:
Collectively evaluated for impairment	23,326	20,698
Total ending loan balance	23,326	20,698
Home Equity Loans and Lines of Credit
Allowance for loan losses:
Collectively evaluated for impairment	1	1
Total ending allowance balance	1	1	1
Loans:
Individually evaluated for impairment	89	148
Collectively evaluated for impairment	9,997	10,945
Total ending loan balance	10,086	11,093
Consumer and other loans
Allowance for loan losses:
Collectively evaluated for impairment	54	47
Total ending allowance balance	54	47	55
Loans:
Collectively evaluated for impairment	9,735	5,311
Total ending loan balance	9,735	5,311
Unallocated
Allowance for loan losses:
Collectively evaluated for impairment	405	354
Total ending allowance balance	$ 405	$ 354	$ 232

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The valuation allowance for financing receivables that are expected to be uncollectible that were collectively evaluated for impairment.

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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 of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for loans and leases covered under loss sharing agreements.

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

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