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Investment Securities-Investments Classified by Contractual Maturity Date (Details) - USD ($) $ in Thousands | Dec. 31, 2020 | Mar. 31, 2020
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Available-for-sale Securities, Debt Maturities, Amortized Cost Basis, Fiscal Year Maturity |  |
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, after One Through Five Years, Amortized Cost | $ 3,761 |
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, after Five Through Ten Years, Amortized Cost | 6,043 |
Debt Securities, Available-for-sale, Allocated and Single Maturity Date, Maturity, after 10 Years, Amortized Cost | 44,149 |
Available-for-sale Securities, Amortized Cost Basis | 99,814 | $ 64,897
Debt Securities, Available-for-sale, Amortized Cost | 99,814 |
Available-for-sale Securities, Debt Maturities, Fair Value, Fiscal Year Maturity |  |
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, after One Through Five Years, Fair Value | 3,756 |
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, after Five Through Ten Years, Fair Value | 5,992 |
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, after 10 Years, Fair Value | 44,614 |
Available-for-sale Securities | 100,181 | 65,829
Available-for-sale | $ 100,181 | 65,829
Available-for-sale Securities, Debt Maturities, after One Through Five Years, Weighted Average Rate | 3.04% |
Available-for-sale Securities, Debt Maturities, after Five Through Ten Years, Weighted Average Rate | 1.34% |
Available-for-sale Securities, Debt Maturities, after Ten Years, Weighted Average Rate | 1.85% |
Available-for-sale Securities, Debt Maturities, Weighted Average Rate | 1.59% |
Held-to-maturity Securities, Debt Maturities, Net Carrying Amount |  |
Debt Securities, Held-to-Maturity, Amortized Cost, Maturity, Allocated and Single Maturity Date, after Year One Through Five | $ 1,000 |
Held-to-maturity | 9,164 | 10,151
Held-to-maturity Securities, Debt Maturities, Fair Value, Fiscal Year Maturity |  |
Debt Securities, Held-to-Maturity, Fair Value, Maturity, Allocated and Single Maturity Date, after Year One Through Five | 1,000 |
Held-to-maturity, Fair Value | $ 9,551 | $ 10,564
Debt Securities, Held-to-Maturity, Weighted Average Yield, Maturity, after Year One Through Five | 4.15% |
Held-to-maturity Securities, Debt Maturities, Weighted Average Rate | 2.60% |

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- Definition Amortized cost 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 320 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=121645371&loc=d3e27161-111563 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=121558606&loc=SL82898722-210454 + Details
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