Investment Securities Investment Securities-Unrealized Gain (Loss) on Investments (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Mar. 31, 2019
Schedule of Held-to-maturity Securities [Line Items]
Held-to-maturity	$ 10,892	$ 11,137
Held-to-maturity, Gross Unrealized Gains	154	57
Held-to-maturity, Gross Unrealized Losses	19	87
Held-to-maturity, Fair Value	11,027	11,107
Debt Securities, Available-for-sale [Line Items]
Available-for-sale, Amortized Cost	78,467	80,784
Available-for-sale, Gross Unrealized Gains	499	225
Available-for-sale, Gross Unrealized Losses	575	1,164
Available-for-sale, Fair Value	78,391	79,845
Government National Mortgage Association (GNMA)
Schedule of Held-to-maturity Securities [Line Items]
Held-to-maturity	1,155	1,214
Held-to-maturity, Gross Unrealized Gains	61	40
Held-to-maturity, Gross Unrealized Losses	0	0
Held-to-maturity, Fair Value	1,216	1,254
Debt Securities, Available-for-sale [Line Items]
Available-for-sale, Amortized Cost	4,193	4,443
Available-for-sale, Gross Unrealized Gains	53	25
Available-for-sale, Gross Unrealized Losses	41	86
Available-for-sale, Fair Value	4,205	4,382
Federal Home Loan Mortgage Corporation (FHLMC)
Debt Securities, Available-for-sale [Line Items]
Available-for-sale, Amortized Cost	10,756	11,104
Available-for-sale, Gross Unrealized Gains	138	69
Available-for-sale, Gross Unrealized Losses	65	148
Available-for-sale, Fair Value	10,829	11,025
Federal National Mortgage Association (FNMA)
Schedule of Held-to-maturity Securities [Line Items]
Held-to-maturity	8,737	8,923
Held-to-maturity, Gross Unrealized Gains	77	0
Held-to-maturity, Gross Unrealized Losses	19	87
Held-to-maturity, Fair Value	8,795	8,836
Debt Securities, Available-for-sale [Line Items]
Available-for-sale, Amortized Cost	26,264	27,094
Available-for-sale, Gross Unrealized Gains	275	131
Available-for-sale, Gross Unrealized Losses	323	617
Available-for-sale, Fair Value	26,216	26,608
Mortgage-backed securities
Schedule of Held-to-maturity Securities [Line Items]
Held-to-maturity	9,892	10,137
Held-to-maturity, Gross Unrealized Gains	138	40
Held-to-maturity, Gross Unrealized Losses	19	87
Held-to-maturity, Fair Value	10,011	10,090
Debt Securities, Available-for-sale [Line Items]
Available-for-sale, Amortized Cost	41,213	42,641
Available-for-sale, Gross Unrealized Gains	466	225
Available-for-sale, Gross Unrealized Losses	429	851
Available-for-sale, Fair Value	41,250	42,015
US Government Agency Securities
Debt Securities, Available-for-sale [Line Items]
Available-for-sale, Amortized Cost	32,207	33,089
Available-for-sale, Gross Unrealized Gains	15	0
Available-for-sale, Gross Unrealized Losses	131	236
Available-for-sale, Fair Value	32,091	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	16	17
Held-to-maturity, Gross Unrealized Losses	0	0
Held-to-maturity, Fair Value	1,016	1,017
Debt Securities, Available-for-sale [Line Items]
Available-for-sale, Amortized Cost	5,047	5,054
Available-for-sale, Gross Unrealized Gains	18	0
Available-for-sale, Gross Unrealized Losses	15	77
Available-for-sale, Fair Value	$ 5,050	$ 4,977

Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

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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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