Allowance for Loan Losses (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Mar. 31, 2019
Financing Receivable, Allowance for Credit Loss [Line Items]
Allowance for loan losses - Beginning Balance	$ 4,625	$ 4,792	$ 4,646	$ 5,126
Charge-offs	(33)	(503)	(162)	(1,093)
Recoveries	7	845	107	1,047
Provision for loan losses	8	(332)	16	(278)
Allowance for loan losses - Ending Balance	4,607	4,802	4,607	4,802
Allowance for Loan Losses, Collectively Evaluated for Impairment	4,439		4,439		$ 4,457
Allowance for Loan Losses, Individually Evaluated for Impairment	168		168		189
Loans, gross	422,319		422,319		428,828
Loans Receivable, Collectively Evaluated for Impairment	413,394		413,394		416,459
Loans Receivable, Individually Evaluated for Impairment	8,925		8,925		12,369
One-to-four family
Financing Receivable, Allowance for Credit Loss [Line Items]
Allowance for loan losses - Beginning Balance	1,289	1,481	1,274	1,210
Charge-offs	(12)	(6)	(12)	(151)
Recoveries	0	186	8	186
Provision for loan losses	(96)	(198)	(89)	218
Allowance for loan losses - Ending Balance	1,181	1,463	1,181	1,463
Allowance for Loan Losses, Collectively Evaluated for Impairment	1,023		1,023		1,103
Allowance for Loan Losses, Individually Evaluated for Impairment	158		158		171
Loans, gross	113,352		113,352		109,926
Loans Receivable, Collectively Evaluated for Impairment	108,250		108,250		104,509
Loans Receivable, Individually Evaluated for Impairment	5,102		5,102		5,417
Multifamily
Financing Receivable, Allowance for Credit Loss [Line Items]
Allowance for loan losses - Beginning Balance	884	939	885	1,819
Charge-offs	0	0	0	(100)
Recoveries	0	0	0	158
Provision for loan losses	36	(65)	35	(1,003)
Allowance for loan losses - Ending Balance	920	874	920	874
Allowance for Loan Losses, Collectively Evaluated for Impairment	920		920		885
Allowance for Loan Losses, Individually Evaluated for Impairment	0		0		0
Loans, gross	84,072		84,072		86,886
Loans Receivable, Collectively Evaluated for Impairment	83,694		83,694		83,672
Loans Receivable, Individually Evaluated for Impairment	378		378		3,214
Commercial real estate
Financing Receivable, Allowance for Credit Loss [Line Items]
Allowance for loan losses - Beginning Balance	695	702	766	1,052
Charge-offs	0	0	0	0
Recoveries	0	0	0	0
Provision for loan losses	(4)	36	(75)	(314)
Allowance for loan losses - Ending Balance	691	738	691	738
Allowance for Loan Losses, Collectively Evaluated for Impairment	691		691		766
Allowance for Loan Losses, Individually Evaluated for Impairment	0		0		0
Loans, gross	135,424		135,424		131,292
Loans Receivable, Collectively Evaluated for Impairment	135,424		135,424		130,816
Loans Receivable, Individually Evaluated for Impairment	0		0		476
Business
Financing Receivable, Allowance for Credit Loss [Line Items]
Allowance for loan losses - Beginning Balance	1,491	1,530	1,330	1,003
Charge-offs	(13)	(490)	(69)	(830)
Recoveries	7	658	97	667
Provision for loan losses	(1)	(320)	126	538
Allowance for loan losses - Ending Balance	1,484	1,378	1,484	1,378
Allowance for Loan Losses, Collectively Evaluated for Impairment	1,474		1,474		1,312
Allowance for Loan Losses, Individually Evaluated for Impairment	10		10		18
Loans, gross	85,883		85,883		96,661
Loans Receivable, Collectively Evaluated for Impairment	82,438		82,438		93,399
Loans Receivable, Individually Evaluated for Impairment	3,445		3,445		3,262
Consumer
Financing Receivable, Allowance for Credit Loss [Line Items]
Allowance for loan losses - Beginning Balance	248	140	154	18
Charge-offs	(8)	(7)	(81)	(12)
Recoveries	0	1	2	36
Provision for loan losses	(9)	(12)	156	80
Allowance for loan losses - Ending Balance	231	122	231	122
Allowance for Loan Losses, Collectively Evaluated for Impairment	231		231		154
Allowance for Loan Losses, Individually Evaluated for Impairment	0		0		0
Loans, gross	3,588		3,588		4,063
Loans Receivable, Collectively Evaluated for Impairment	3,588		3,588		4,063
Loans Receivable, Individually Evaluated for Impairment	0		0		0
Unallocated
Financing Receivable, Allowance for Credit Loss [Line Items]
Allowance for loan losses - Beginning Balance	18	0	237	24
Charge-offs	0	0	0	0
Recoveries	0	0	0	0
Provision for loan losses	82	227	(137)	203
Allowance for loan losses - Ending Balance	100	$ 227	100	$ 227
Allowance for Loan Losses, Collectively Evaluated for Impairment	100		100		237
Allowance for Loan Losses, Individually Evaluated for Impairment	0		0		0
Loans, gross	0		0		0
Loans Receivable, Collectively Evaluated for Impairment	0		0		0
Loans Receivable, Individually Evaluated for Impairment	$ 0		$ 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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