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Investment Securities Text Tags (Details) | 6 Months Ended |
--- | --- | ---
Sep. 30, 2021 USD ($) | Sep. 30, 2020 USD ($) | Mar. 31, 2021 USD ($)
Schedule of Investments [Line Items] |  |  |
Debt Securities, Available-for-sale, Unrealized Loss Position, Number of Positions | 14 |  | 15
Proceeds from Sale of Debt Securities, Available-for-sale | $ 0 | $ 30,190,000 |
Debt Securities, Available-for-sale | $ 79,853,000 |  | $ 86,507,000
Percentage Available-for-sale Securities | 93.40% |  |
Debt Securities, Held-to-maturity | $ 5,623,000 |  | 7,807,000
Percentage Held-to-maturity Securities | 6.60% |  |
Trading | $ 0 |  |
Mortgage-backed securities |  |  |
Schedule of Investments [Line Items] |  |  |
Percentage Available-for-Sale, Continuos Unrealized Loss Position | 49.80% |  |
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Number of Positions | 2 |  |
Debt Securities, Available-for-sale | $ 39,644,000 |  | 43,421,000
US Government Agency Securities |  |  |
Schedule of Investments [Line Items] |  |  |
Percentage Available-for-Sale, Continuos Unrealized Loss Position | 23.60% |  |
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Number of Positions | 3 |  |
Debt Securities, Available-for-sale | $ 17,404,000 |  | 18,631,000
Municipal Securities |  |  |
Schedule of Investments [Line Items] |  |  |
Percentage Available-for-Sale, Continuos Unrealized Loss Position | 19.90% |  |
Debt Securities, Available-for-sale | $ 17,457,000 |  | $ 16,610,000

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- Definition Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale). + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03(6)) -URI http://asc.fasb.org/extlink&oid=120398452&loc=d3e534808-122878 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 30 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=124258926&loc=SL82898722-210454 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 45 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=124260329&loc=d3e26610-111562 Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (aa) -URI http://asc.fasb.org/extlink&oid=123581744&loc=d3e27161-111563 + Details
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