Allowance for Loan Losses (Details) - USD ($) $ in Thousands	3 Months Ended
Jun. 30, 2020	Jun. 30, 2019	Mar. 31, 2020
Financing Receivable, Allowance for Credit Loss [Line Items]
Allowance for loan losses - Beginning Balance	$ 4,946	$ 4,646
Charge-offs	(10)	(67)
Recoveries	2	90
Provision for loan losses	(102)	1
Allowance for loan losses - Ending Balance	4,836	4,670
Allowance for Loan Losses, Collectively Evaluated for Impairment	4,725		$ 4,780
Allowance for Loan Losses, Individually Evaluated for Impairment	111		166
Loans, gross	458,571		428,732
Loans Receivable, Collectively Evaluated for Impairment	446,312		420,282
Loans Receivable, Individually Evaluated for Impairment	12,259		8,450
One-to-four family
Financing Receivable, Allowance for Credit Loss [Line Items]
Allowance for loan losses - Beginning Balance	1,055	1,274
Charge-offs	0	0
Recoveries	0	0
Provision for loan losses	(83)	(42)
Allowance for loan losses - Ending Balance	972	1,232
Allowance for Loan Losses, Collectively Evaluated for Impairment	870		899
Allowance for Loan Losses, Individually Evaluated for Impairment	103		156
Loans, gross	97,976		107,528
Loans Receivable, Collectively Evaluated for Impairment	93,512		102,902
Loans Receivable, Individually Evaluated for Impairment	4,464		4,626
Multifamily
Financing Receivable, Allowance for Credit Loss [Line Items]
Allowance for loan losses - Beginning Balance	1,011	885
Charge-offs	0	0
Recoveries	0	0
Provision for loan losses	(100)	(10)
Allowance for loan losses - Ending Balance	911	875
Allowance for Loan Losses, Collectively Evaluated for Impairment	911		1,011
Allowance for Loan Losses, Individually Evaluated for Impairment	0		0
Loans, gross	92,125		89,887
Loans Receivable, Collectively Evaluated for Impairment	91,752		89,512
Loans Receivable, Individually Evaluated for Impairment	373		375
Commercial real estate
Financing Receivable, Allowance for Credit Loss [Line Items]
Allowance for loan losses - Beginning Balance	812	766
Charge-offs	0	0
Recoveries	0	0
Provision for loan losses	143	(98)
Allowance for loan losses - Ending Balance	955	668
Allowance for Loan Losses, Collectively Evaluated for Impairment	955		812
Allowance for Loan Losses, Individually Evaluated for Impairment	0		0
Loans, gross	148,786		142,410
Loans Receivable, Collectively Evaluated for Impairment	144,647		142,410
Loans Receivable, Individually Evaluated for Impairment	4,139		0
Business
Financing Receivable, Allowance for Credit Loss [Line Items]
Allowance for loan losses - Beginning Balance	1,567	1,330
Charge-offs	(10)	0
Recoveries	0	88
Provision for loan losses	(46)	(18)
Allowance for loan losses - Ending Balance	1,511	1,400
Allowance for Loan Losses, Collectively Evaluated for Impairment	1,502		1,557
Allowance for Loan Losses, Individually Evaluated for Impairment	8		10
Loans, gross	116,678		85,659
Loans Receivable, Collectively Evaluated for Impairment	113,395		82,210
Loans Receivable, Individually Evaluated for Impairment	3,283		3,449
Consumer
Financing Receivable, Allowance for Credit Loss [Line Items]
Allowance for loan losses - Beginning Balance	212	154
Charge-offs	0	(67)
Recoveries	2	2
Provision for loan losses	(12)	151
Allowance for loan losses - Ending Balance	202	240
Allowance for Loan Losses, Collectively Evaluated for Impairment	202		212
Allowance for Loan Losses, Individually Evaluated for Impairment	0		0
Loans, gross	3,006		3,248
Loans Receivable, Collectively Evaluated for Impairment	3,006		3,248
Loans Receivable, Individually Evaluated for Impairment	0		0
Unallocated
Financing Receivable, Allowance for Credit Loss [Line Items]
Allowance for loan losses - Beginning Balance	289	237
Charge-offs	0	0
Recoveries	0	0
Provision for loan losses	(4)	18
Allowance for loan losses - Ending Balance	285	$ 255
Allowance for Loan Losses, Collectively Evaluated for Impairment	285		289
Allowance for Loan Losses, Individually Evaluated for Impairment	0		0
Loans, gross	0		0
Loans Receivable, Collectively Evaluated for Impairment	0		0
Loans Receivable, Individually Evaluated for Impairment	$ 0		$ 0

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

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