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Investment Securities Text Tag (Details) | 12 Months Ended
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Mar. 31, 2022 USD ($) | Mar. 31, 2021 USD ($)
Investments, Debt and Equity Securities [Abstract] |  |
Available-for-sale | $ 67,596,000 | $ 86,507,000
Percentage Available-for-sale Securities | 92.80% |
Debt Securities, Held-to-maturity | $ 5,254,000 | 7,807,000
Percentage Held-to-maturity Securities | 7.20% |
Debt Securities, Trading, and Equity Securities, FV-NI | $ 0 |
Equity securities | 1,100,000 |
Proceeds from sales of investments: Available-for-sale | 0 | $ 37,802,000
Pledged Financial Instruments, Not Separately Reported, Securities for Federal Home Loan Bank | $ 5,900,000 |
Debt Securities, Available-for-sale, Unrealized Loss Position, Number of Positions | 23 | 15
Mortgage-Backed Securities |  |
Investments, Debt and Equity Securities [Abstract] |  |
Available-for-sale | $ 33,579,000 | $ 43,421,000
Debt Securities, Held-to-maturity | $ 5,254,000 |
Debt Securities, Available-for-sale [Line Items] |  |
Percentage Available-for-Sale, Continuous Unrealized Loss Position | 49.40% |
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Number of Positions | 4 |
US Government Agency Securities |  |
Investments, Debt and Equity Securities [Abstract] |  |
Available-for-sale | $ 13,785,000 | 18,631,000
Debt Securities, Available-for-sale [Line Items] |  |
Percentage Available-for-Sale, Continuous Unrealized Loss Position | 20.50% |
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Number of Positions | 3 |
Corporate Bonds |  |
Investments, Debt and Equity Securities [Abstract] |  |
Available-for-sale | $ 4,121,000 | 4,481,000
Debt Securities, Available-for-sale [Line Items] |  |
Percentage Available-for-Sale, Continuous Unrealized Loss Position | 6.10% |
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Number of Positions | 1 |
Municipal Bonds |  |
Investments, Debt and Equity Securities [Abstract] |  |
Available-for-sale | $ 15,768,000 | $ 16,610,000
Debt Securities, Available-for-sale [Line Items] |  |
Percentage Available-for-Sale, Continuous Unrealized Loss Position | 23.50% |
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Number of Positions | 1 |

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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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- Definition Number of investments in debt securities measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in continuous unrealized loss position for 12 months or longer, without an allowance for credit loss. Includes beneficial interest in securitized financial asset. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 30 -Section 50 -Paragraph 4 -Subparagraph (b)(3) -URI http://asc.fasb.org/extlink&oid=124269663&loc=SL82922888-210455 + Details
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