Loans Receivable and Allowance for Loan Losses, Classes of Loan Portfolio by Aging Categories of Performing and Nonaccrual Loans (Details) - USD ($)	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Classes of the loan portfolio summarized by the aging categories of performing loans and nonaccrual loans [Abstract]
Total past due	$ 5,833,000	$ 5,260,000
Current	639,852,000	677,089,000
Loans receivable	645,685,000	682,349,000
Non-accrual	4,242,000	4,656,000
Interest which would have been recorded on the loans in nonaccrual status	537,000	716,000
Actual interest income recorded on nonaccrual loans	184,000	273,000
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	3,183,000	1,561,000
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	185,000
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	2,465,000	3,699,000
Residential Mortgage [Member]
Classes of the loan portfolio summarized by the aging categories of performing loans and nonaccrual loans [Abstract]
Total past due	5,464,000	2,854,000
Current	262,688,000	271,905,000
Loans receivable	268,152,000	274,759,000
Non-accrual	3,766,000	2,580,000
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	3,183,000	1,060,000
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	81,000
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	2,200,000	1,794,000
Commercial [Member]
Classes of the loan portfolio summarized by the aging categories of performing loans and nonaccrual loans [Abstract]
Total past due		430,000
Current	43,127,000	35,454,000
Loans receivable	43,127,000	35,884,000
Non-accrual		430,000
Commercial [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		430,000
Commercial Real Estate [Member]
Classes of the loan portfolio summarized by the aging categories of performing loans and nonaccrual loans [Abstract]
Total past due	126,000	797,000
Current	227,886,000	241,896,000
Loans receivable	228,012,000	242,693,000
Non-accrual	237,000	660,000
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		137,000
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	126,000	660,000
ADC [Member]
Classes of the loan portfolio summarized by the aging categories of performing loans and nonaccrual loans [Abstract]
Total past due	89,000	642,000
Current	92,733,000	113,898,000
Loans receivable	92,822,000	114,540,000
Non-accrual	89,000	558,000
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		255,000
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	89,000
ADC [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		387,000
Home Equity/2nds [Member]
Classes of the loan portfolio summarized by the aging categories of performing loans and nonaccrual loans [Abstract]
Total past due	139,000	524,000
Current	11,892,000	12,862,000
Loans receivable	12,031,000	13,386,000
Non-accrual	150,000	428,000
Home Equity/2nds [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		96,000
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	139,000	428,000
Consumer [Member]
Classes of the loan portfolio summarized by the aging categories of performing loans and nonaccrual loans [Abstract]
Total past due	15,000	13,000
Current	1,526,000	1,074,000
Loans receivable	1,541,000	1,087,000
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		$ 13,000
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	$ 15,000

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

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Amount of financing receivable not past due.

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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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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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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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