Allowance for Loan Loss (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2022	Mar. 31, 2021	Dec. 31, 2021
Allowance for loan losses:
Beginning Balance	$ 1,841	$ 1,821	$ 1,821
Charge-offs	(50)	(108)	(647)
Recoveries	33	33	127
Provision (credit) for loan losses	150	135	540
Ending balance	1,974	1,881	1,841
Ending balance: related to loans individually evaluated for impairment	12	296	19
Ending balance: related to loans collectively evaluated for impairment	1,962	1,585	1,822
Loans receivable - Ending balance	261,575	271,994	264,658
Loans receivable - Ending balance: individually evaluated for impairment	2,814	7,624	3,187
Loans receivable - Ending balance: collectively evaluated for impairment	258,761	264,370	261,471
Residential
Allowance for loan losses:
Loans receivable - Ending balance	111,291		113,061
Residential \| One- to four-family
Allowance for loan losses:
Beginning Balance	688	457	457
Charge-offs	(10)	(3)	(117)
Recoveries	15	1	28
Provision (credit) for loan losses	46	85	320
Ending balance	739	540	688
Ending balance: related to loans individually evaluated for impairment		18	7
Ending balance: related to loans collectively evaluated for impairment	739	522	681
Loans receivable - Ending balance	111,291	122,533	113,061
Loans receivable - Ending balance: individually evaluated for impairment	2,158	2,551	2,576
Loans receivable - Ending balance: collectively evaluated for impairment	109,133	119,982	110,485
Commercial
Allowance for loan losses:
Loans receivable - Ending balance	33,607		34,462
Commercial \| Real estate - nonresidential
Allowance for loan losses:
Beginning Balance	630	319	319
Charge-offs		(51)	(386)
Recoveries			16
Provision (credit) for loan losses	14	120	681
Ending balance	644	388	630
Ending balance: related to loans individually evaluated for impairment		66
Ending balance: related to loans collectively evaluated for impairment	644	322	630
Loans receivable - Ending balance	20,857	24,405	21,478
Loans receivable - Ending balance: individually evaluated for impairment	416	2,788	416
Loans receivable - Ending balance: collectively evaluated for impairment	20,441	21,617	21,062
Commercial \| Multi-family
Allowance for loan losses:
Beginning Balance	2	26	26
Recoveries		6	12
Provision (credit) for loan losses	1	(21)	(36)
Ending balance	3	11	2
Ending balance: related to loans collectively evaluated for impairment	3	11	2
Loans receivable - Ending balance	452	2,331	456
Loans receivable - Ending balance: collectively evaluated for impairment	452	2,331	456
Commercial \| Commercial business
Allowance for loan losses:
Beginning Balance	161	617	617
Charge-offs		(17)	(84)
Recoveries		7	7
Provision (credit) for loan losses	48	(77)	(379)
Ending balance	209	530	161
Ending balance: related to loans individually evaluated for impairment	12	210	12
Ending balance: related to loans collectively evaluated for impairment	197	320	149
Loans receivable - Ending balance	12,298	19,576	12,528
Loans receivable - Ending balance: individually evaluated for impairment	128	2,177	128
Loans receivable - Ending balance: collectively evaluated for impairment	12,170	17,399	12,400
Consumer
Allowance for loan losses:
Loans receivable - Ending balance	116,677		117,135
Consumer \| Home equity and junior liens
Allowance for loan losses:
Beginning Balance	39	46	46
Charge-offs		(2)	(2)
Provision (credit) for loan losses	4	4	(5)
Ending balance	43	48	39
Ending balance: related to loans collectively evaluated for impairment	43	48	39
Loans receivable - Ending balance	10,433	10,365	9,701
Loans receivable - Ending balance: individually evaluated for impairment	112	103	67
Loans receivable - Ending balance: collectively evaluated for impairment	10,321	10,262	9,634
Consumer \| Manufactured homes
Allowance for loan losses:
Beginning Balance	102	76	76
Provision (credit) for loan losses	14	5	26
Ending balance	116	81	102
Ending balance: related to loans collectively evaluated for impairment	116	81	102
Loans receivable - Ending balance	48,116	46,608	47,717
Loans receivable - Ending balance: collectively evaluated for impairment	48,116	46,608	47,717
Consumer \| Automobile
Allowance for loan losses:
Beginning Balance	107	127	127
Charge-offs	(40)	(2)	(12)
Recoveries	17	10	48
Provision (credit) for loan losses	23	2	(56)
Ending balance	107	137	107
Ending balance: related to loans collectively evaluated for impairment	107	137	107
Loans receivable - Ending balance	22,025	22,421	22,666
Loans receivable - Ending balance: collectively evaluated for impairment	22,025	22,421	22,666
Consumer \| Student
Allowance for loan losses:
Beginning Balance	64	69	69
Recoveries	1	1	3
Provision (credit) for loan losses	(1)	1	(8)
Ending balance	64	71	64
Ending balance: related to loans collectively evaluated for impairment	64	71	64
Loans receivable - Ending balance	2,102	2,304	2,096
Loans receivable - Ending balance: collectively evaluated for impairment	2,102	2,304	2,096
Consumer \| Recreational Vehicle
Allowance for loan losses:
Charge-offs			(1)
Recoveries		7	8
Provision (credit) for loan losses		(7)	(7)
Loans receivable - Ending balance	28,692	17,043	29,463
Loans receivable - Ending balance: collectively evaluated for impairment	28,692	17,043	29,463
Consumer \| Other consumer
Allowance for loan losses:
Beginning Balance	48	84	84
Charge-offs		(33)	(45)
Recoveries		1	5
Provision (credit) for loan losses	1	23	4
Ending balance	49	75	48
Ending balance: related to loans individually evaluated for impairment		2
Ending balance: related to loans collectively evaluated for impairment	49	73	48
Loans receivable - Ending balance	5,309	4,408	5,492
Loans receivable - Ending balance: individually evaluated for impairment		5
Loans receivable - Ending balance: collectively evaluated for impairment	$ 5,309	$ 4,403	$ 5,492

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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The balance of financing receivables that were collectively 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 fees, of loans and leases receivable. Excludes loans and leases covered under loss sharing agreements.

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Amount of expense related loan transactions, lease transactions, credit loss from transactions other than loan and lease transactions, and other loss based on assessment of uncollectability from the counterparty to reduce the account to their net realizable value.

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