Loans Receivable and Allowance for Loan Losses (Schedule of allowance for credit losses on financing receivables) (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2020	Dec. 31, 2019
Allowance for Credit Losses:
Beginning Balance	$ 769	$ 768
Charge-offs	(1)	(18)
Recoveries		6
Provision	10	13
Ending Balance	778	769
Ending Balance: Individually Evaluated for Impairment	113	85
Ending Balance: Collectively Evaluated for Impairment	665	684
Loans Receivable:
Ending Balance	109,418	105,748
Ending Balance: Individually Evaluated for Impairment	1,114	828
Ending Balance: Collectively Evaluated for Impairment	108,304	104,920
Real Estate \| Commercial
Allowance for Credit Losses:
Beginning Balance	96	113
Recoveries		5
Provision		(22)
Ending Balance	96	96
Ending Balance: Collectively Evaluated for Impairment	96	96
Loans Receivable:
Ending Balance	21,976	22,349
Ending Balance: Collectively Evaluated for Impairment	21,976	22,349
Real Estate \| Land
Allowance for Credit Losses:
Beginning Balance	18	23
Provision	1	(5)
Ending Balance	19	18
Ending Balance: Individually Evaluated for Impairment	1
Ending Balance: Collectively Evaluated for Impairment	18	18
Loans Receivable:
Ending Balance	2,390	2,200
Ending Balance: Individually Evaluated for Impairment	12
Ending Balance: Collectively Evaluated for Impairment	2,378	2,200
Real Estate \| One-to-Four Family
Allowance for Credit Losses:
Beginning Balance	516	519
Provision	(13)	(3)
Ending Balance	502	516
Ending Balance: Individually Evaluated for Impairment	112	85
Ending Balance: Collectively Evaluated for Impairment	390	431
Loans Receivable:
Ending Balance	74,635	72,273
Ending Balance: Individually Evaluated for Impairment	1,102	828
Ending Balance: Collectively Evaluated for Impairment	73,533	71,445
Real Estate \| Construction
Allowance for Credit Losses:
Beginning Balance	20	16
Provision	3	4
Ending Balance	23	20
Ending Balance: Collectively Evaluated for Impairment	23	20
Loans Receivable:
Ending Balance	4,848	4,259
Ending Balance: Collectively Evaluated for Impairment	4,848	4,259
Real Estate \| Multi-family
Allowance for Credit Losses:
Beginning Balance	6	5
Provision	1	1
Ending Balance	7	6
Ending Balance: Collectively Evaluated for Impairment	7	6
Loans Receivable:
Ending Balance	2,069	2,086
Ending Balance: Collectively Evaluated for Impairment	2,069	2,086
Consumer
Allowance for Credit Losses:
Beginning Balance	26	9
Charge-offs	(1)	(18)
Recoveries		1
Provision	6	34
Ending Balance	31	26
Ending Balance: Collectively Evaluated for Impairment	31	26
Loans Receivable:
Ending Balance	355	246
Ending Balance: Collectively Evaluated for Impairment	355	246
Commercial
Allowance for Credit Losses:
Beginning Balance	87	83
Provision	12	4
Ending Balance	99	87
Ending Balance: Collectively Evaluated for Impairment	99	87
Loans Receivable:
Ending Balance	3,145	2,335
Ending Balance: Collectively Evaluated for Impairment	$ 3,145	$ 2,335

Amount of recovery of loans and lease receivables which had previously been fully or partially written-off as bad debts.

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Amount of loans and leases that have been written off from both loan receivables and allowance reserve for credit loss.

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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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Amount of valuation allowance for financing receivables that are expected to be uncollectible that were individually evaluated for impairment.

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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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 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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Amount of expense related to estimated loss from loan and lease transactions.

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