Loans Receivable and the Allowance for Loan Losses - Allowance (Details)	3 Months Ended	12 Months Ended
Mar. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)
Allowance for Loan Losses:
Beginning Balance	$ 858,000	$ 850,000
Recoveries		8,000
Ending Balance	858,000	858,000
Ending Balance: Collectively Evaluated for Impairment	858,000	858,000
Loans Receivable: Ending Balance	76,273,000	75,431,000
Ending Balance: Collectively Evaluated for Impairment	76,273,000	75,431,000
Allowance for loan losses, unallocated portion	858,000	858,000
Loan balances outstanding on non-accrual status	0	0
Mortgage - 1-4 Family
Allowance for Loan Losses:
Beginning Balance	752,000	818,000
Recoveries		8,000
Provision (Credit)	4,000	(74,000)
Ending Balance	756,000	752,000
Ending Balance: Collectively Evaluated for Impairment	756,000	752,000
Loans Receivable: Ending Balance	65,686,000	66,356,000
Ending Balance: Collectively Evaluated for Impairment	65,686,000	66,356,000
Allowance for loan losses, unallocated portion	756,000	752,000
Mortgage - Multifamily
Allowance for Loan Losses:
Beginning Balance	21,000	22,000
Provision (Credit)	(3,000)	(1,000)
Ending Balance	18,000	21,000
Ending Balance: Collectively Evaluated for Impairment	18,000	21,000
Loans Receivable: Ending Balance	2,390,000	2,780,000
Ending Balance: Collectively Evaluated for Impairment	2,390,000	2,780,000
Allowance for loan losses, unallocated portion	18,000	21,000
Mortgage - Construction and Land
Allowance for Loan Losses:
Beginning Balance	63,000	6,000
Provision (Credit)	(1,000)	57,000
Ending Balance	62,000	63,000
Ending Balance: Collectively Evaluated for Impairment	62,000	63,000
Loans Receivable: Ending Balance	6,499,000	4,576,000
Ending Balance: Collectively Evaluated for Impairment	6,499,000	4,576,000
Allowance for loan losses, unallocated portion	62,000	63,000
Mortgage - Commercial real estate
Allowance for Loan Losses:
Beginning Balance	22,000	4,000
Provision (Credit)		18,000
Ending Balance	22,000	22,000
Ending Balance: Collectively Evaluated for Impairment	22,000	22,000
Loans Receivable: Ending Balance	1,468,000	1,480,000
Ending Balance: Collectively Evaluated for Impairment	1,468,000	1,480,000
Allowance for loan losses, unallocated portion	22,000	22,000
Consumer Loans
Allowance for Loan Losses:
Loans Receivable: Ending Balance	230,000	239,000
Ending Balance: Collectively Evaluated for Impairment	230,000	239,000
Unallocated finance receivable
Allowance for Loan Losses:
Beginning Balance	477,000
Ending Balance	481,000	477,000
Allowance for loan losses, unallocated portion	$ 481,000	$ 477,000
Maximum
Allowance for Loan Losses:
Stressed debt service coverage ratio	1.20

Stressed debt service coverage ratio.

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Amount of allowance for credit loss on financing receivable. Excludes allowance for financing receivable covered under loss sharing agreement.

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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 increase in allowance for credit loss on financing receivable from recovery.

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The balance of financing receivables that were collectively evaluated for impairment.

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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 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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