Loans Receivable and Allowance for Loan Losses, Classes of Loan Portfolio by Aging Categories of Performing and Nonaccrual Loans (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019	Dec. 31, 2019
Classes of the loan portfolio summarized by the aging categories of performing loans and nonaccrual loans [Abstract]
Total past due	$ 8,648		$ 5,833
Current	630,011		642,599
Total loans	638,659	$ 677,115	648,432
Non-accrual	7,246		4,242
Interest which would have been recorded on the loans in nonaccrual status	467	412
Actual interest income recorded on nonaccrual loans	60	22
30 to 59 Days Past Due [Member]
Classes of the loan portfolio summarized by the aging categories of performing loans and nonaccrual loans [Abstract]
Total past due	3,288		3,183
60 to 89 Days Past Due [Member]
Classes of the loan portfolio summarized by the aging categories of performing loans and nonaccrual loans [Abstract]
Total past due	85		185
90+ Days Past Due [Member]
Classes of the loan portfolio summarized by the aging categories of performing loans and nonaccrual loans [Abstract]
Total past due	5,275		2,465
Residential Mortgage [Member]
Classes of the loan portfolio summarized by the aging categories of performing loans and nonaccrual loans [Abstract]
Total past due	7,277		5,464
Current	253,704		264,190
Total loans	260,981	270,979	269,654
Non-accrual	6,696		3,766
Residential Mortgage [Member] \| 30 to 59 Days Past Due [Member]
Classes of the loan portfolio summarized by the aging categories of performing loans and nonaccrual loans [Abstract]
Total past due	2,176		3,183
Residential Mortgage [Member] \| 60 to 89 Days Past Due [Member]
Classes of the loan portfolio summarized by the aging categories of performing loans and nonaccrual loans [Abstract]
Total past due	85		81
Residential Mortgage [Member] \| 90+ Days Past Due [Member]
Classes of the loan portfolio summarized by the aging categories of performing loans and nonaccrual loans [Abstract]
Total past due	5,016		2,200
Commercial [Member]
Classes of the loan portfolio summarized by the aging categories of performing loans and nonaccrual loans [Abstract]
Current	43,490		43,127
Total loans	43,490	44,725	43,127
Commercial Real Estate [Member]
Classes of the loan portfolio summarized by the aging categories of performing loans and nonaccrual loans [Abstract]
Total past due	425		126
Current	220,229		229,131
Total loans	220,654	238,618	229,257
Non-accrual	234		237
Commercial Real Estate [Member] \| 30 to 59 Days Past Due [Member]
Classes of the loan portfolio summarized by the aging categories of performing loans and nonaccrual loans [Abstract]
Total past due	299
Commercial Real Estate [Member] \| 90+ Days Past Due [Member]
Classes of the loan portfolio summarized by the aging categories of performing loans and nonaccrual loans [Abstract]
Total past due	126		126
ADC [Member]
Classes of the loan portfolio summarized by the aging categories of performing loans and nonaccrual loans [Abstract]
Total past due	652		89
Current	99,209		92,733
Total loans	99,861	108,933	92,822
Non-accrual	173		89
ADC [Member] \| 30 to 59 Days Past Due [Member]
Classes of the loan portfolio summarized by the aging categories of performing loans and nonaccrual loans [Abstract]
Total past due	652
ADC [Member] \| 60 to 89 Days Past Due [Member]
Classes of the loan portfolio summarized by the aging categories of performing loans and nonaccrual loans [Abstract]
Total past due			89
Home Equity/2nds [Member]
Classes of the loan portfolio summarized by the aging categories of performing loans and nonaccrual loans [Abstract]
Total past due	133		139
Current	12,066		11,892
Total loans	12,199	12,714	12,031
Non-accrual	143		150
Home Equity/2nds [Member] \| 90+ Days Past Due [Member]
Classes of the loan portfolio summarized by the aging categories of performing loans and nonaccrual loans [Abstract]
Total past due	133		139
Consumer [Member]
Classes of the loan portfolio summarized by the aging categories of performing loans and nonaccrual loans [Abstract]
Total past due	161		15
Current	1,313		1,526
Total loans	1,474	$ 1,146	1,541
Consumer [Member] \| 30 to 59 Days Past Due [Member]
Classes of the loan portfolio summarized by the aging categories of performing loans and nonaccrual loans [Abstract]
Total past due	$ 161
Consumer [Member] \| 60 to 89 Days Past Due [Member]
Classes of the loan portfolio summarized by the aging categories of performing loans and nonaccrual loans [Abstract]
Total past due			$ 15

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Reflects the amount of actual interest income recorded on nonaccrual loans.

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Amount of financing receivable on nonaccrual status.

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Amount of financing receivable past due.

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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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