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Investment Securities Text Tag (Details) - USD ($) | 12 Months Ended |
--- | --- | ---
Mar. 31, 2019 | Mar. 31, 2018
Debt Securities, Available-for-sale [Line Items] |  |
Available-for-sale Securities, Amortized Cost Basis | $ 80,784,000 | $ 63,435,000
Cumulative Effect of New Accounting Principle in Period of Adoption | 0 |
Redemption of equity investment | 9,207,000 |
Available-for-sale Securities | $ 79,845,000 | 60,709,000
Percentage Available-for-sale Securities | 87.30% |
Held-to-maturity | $ 11,137,000 | 12,075,000
Percentage Held-to-maturity Securities | 12.20% |
Debt Securities, Trading, and Equity Securities, FV-NI | $ 0 |
Proceeds from Sale and Maturity of Held-to-maturity Securities | 0 |
Financial Instruments, Owned and Pledged as Collateral, at Fair Value | $ 24,600,000 |
Available-for-sale, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions | 35 |
Mortgage-Backed Securities |  |
Debt Securities, Available-for-sale [Line Items] |  |
Available-for-sale Securities, Amortized Cost Basis | $ 42,641,000 | 33,434,000
Percentage Available-for-Sale, Continuous Unrealized Loss Position | 41.50% |
Available-for-sale, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions, Greater than or Equal to One Year | 18 |
Available-for-sale Securities | $ 42,015,000 | 31,827,000
Held-to-maturity | 10,137,000 | 11,075,000
US Government Agency Securities |  |
Debt Securities, Available-for-sale [Line Items] |  |
Available-for-sale Securities, Amortized Cost Basis | $ 33,089,000 | 14,490,000
Percentage Available-for-Sale, Continuous Unrealized Loss Position | 50.80% |
Available-for-sale, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions, Greater than or Equal to One Year | 3 |
Available-for-sale Securities | $ 32,853,000 | 14,232,000
Other investments |  |
Debt Securities, Available-for-sale [Line Items] |  |
Available-for-sale Securities, Amortized Cost Basis |  | 10,433,000
Available-for-sale Securities |  | 9,784,000
Corporate Bonds |  |
Debt Securities, Available-for-sale [Line Items] |  |
Available-for-sale Securities, Amortized Cost Basis | $ 5,054,000 | 5,078,000
Available-for-sale, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions, Greater than or Equal to One Year | 5 |
Available-for-sale Securities | $ 4,977,000 | 4,866,000
Held-to-maturity | 1,000,000 | $ 1,000,000
Accumulated Other Comprehensive Loss |  |
Debt Securities, Available-for-sale [Line Items] |  |
Cumulative Effect of New Accounting Principle in Period of Adoption | $ 721,000 |

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- Definition This item represents the cost of debt and equity securities, which are categorized neither as held-to-maturity nor trading, net of adjustments including accretion, amortization, collection of cash, previous other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments recognized, as defined), and fair value hedge accounting adjustments, if any. + References No definition available. + Details
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- Definition Number of investment positions in available-for-sale investments in a continuous unrealized loss position for which an other-than-temporary impairment (OTTI) has not been recognized in the income statement. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 6 -Subparagraph (b)(3) -URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27290-111563 + Details
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- Definition The fair value as of the balance sheet date of financial instruments and other positions owned by the entity and pledged to counterparties as collateral, including: (1) mortgages, mortgage-backed and asset backed securities; (2) US government and agency obligations; (3) state and municipal government obligations; (4) other sovereign government debt; (5) corporate obligations; (6) corporate equities; (7) principal investments; (8) derivative contracts; and (9) physical commodities. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 860 -SubTopic 30 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=66007379&loc=d3e113888-111728 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 860 -SubTopic 30 -Section 50 -Paragraph 1A -Subparagraph (c)(2) -URI http://asc.fasb.org/extlink&oid=109249958&loc=SL6224234-111729 + Details
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