Investment Securities Investment Securities-Unrealized Gain (Loss) on Investments (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Mar. 31, 2019
Schedule of Held-to-maturity Securities [Line Items]
Held-to-maturity	$ 10,680	$ 11,137
Held-to-maturity, Gross Unrealized Gains	209	57
Held-to-maturity, Gross Unrealized Losses	10	87
Held-to-maturity, Fair Value	10,879	11,107
Debt Securities, Available-for-sale [Line Items]
Available-for-sale, Amortized Cost	75,005	80,784
Available-for-sale, Gross Unrealized Gains	580	225
Available-for-sale, Gross Unrealized Losses	476	1,164
Available-for-sale, Fair Value	75,109	79,845
Government National Mortgage Association (GNMA)
Schedule of Held-to-maturity Securities [Line Items]
Held-to-maturity	1,113	1,214
Held-to-maturity, Gross Unrealized Gains	69	40
Held-to-maturity, Gross Unrealized Losses	0	0
Held-to-maturity, Fair Value	1,182	1,254
Debt Securities, Available-for-sale [Line Items]
Available-for-sale, Amortized Cost	3,907	4,443
Available-for-sale, Gross Unrealized Gains	21	25
Available-for-sale, Gross Unrealized Losses	15	86
Available-for-sale, Fair Value	3,913	4,382
Federal Home Loan Mortgage Corporation (FHLMC)
Debt Securities, Available-for-sale [Line Items]
Available-for-sale, Amortized Cost	10,243	11,104
Available-for-sale, Gross Unrealized Gains	148	69
Available-for-sale, Gross Unrealized Losses	25	148
Available-for-sale, Fair Value	10,366	11,025
Federal National Mortgage Association (FNMA)
Schedule of Held-to-maturity Securities [Line Items]
Held-to-maturity	8,567	8,923
Held-to-maturity, Gross Unrealized Gains	131	0
Held-to-maturity, Gross Unrealized Losses	10	87
Held-to-maturity, Fair Value	8,688	8,836
Debt Securities, Available-for-sale [Line Items]
Available-for-sale, Amortized Cost	25,504	27,094
Available-for-sale, Gross Unrealized Gains	363	131
Available-for-sale, Gross Unrealized Losses	225	617
Available-for-sale, Fair Value	25,642	26,608
Mortgage-backed securities
Schedule of Held-to-maturity Securities [Line Items]
Held-to-maturity	9,680	10,137
Held-to-maturity, Gross Unrealized Gains	200	40
Held-to-maturity, Gross Unrealized Losses	10	87
Held-to-maturity, Fair Value	9,870	10,090
Debt Securities, Available-for-sale [Line Items]
Available-for-sale, Amortized Cost	39,654	42,641
Available-for-sale, Gross Unrealized Gains	532	225
Available-for-sale, Gross Unrealized Losses	265	851
Available-for-sale, Fair Value	39,921	42,015
US Government Agency Securities
Debt Securities, Available-for-sale [Line Items]
Available-for-sale, Amortized Cost	30,310	33,089
Available-for-sale, Gross Unrealized Gains	13	0
Available-for-sale, Gross Unrealized Losses	205	236
Available-for-sale, Fair Value	30,118	32,853
Corporate Bonds
Schedule of Held-to-maturity Securities [Line Items]
Held-to-maturity	1,000	1,000
Held-to-maturity, Gross Unrealized Gains	9	17
Held-to-maturity, Gross Unrealized Losses	0	0
Held-to-maturity, Fair Value	1,009	1,017
Debt Securities, Available-for-sale [Line Items]
Available-for-sale, Amortized Cost	5,041	5,054
Available-for-sale, Gross Unrealized Gains	35	0
Available-for-sale, Gross Unrealized Losses	6	77
Available-for-sale, Fair Value	$ 5,070	$ 4,977

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Amount of accumulated unrecognized gain on investment in debt security measured at amortized cost (held-to-maturity).

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