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Investments - Narrative (Details) $ in Thousands | 1 Months Ended | 3 Months Ended | 12 Months Ended
--- | --- | --- | ---
Mar. 31, 2020 | Mar. 31, 2022 USD ($) security | Mar. 31, 2022 USD ($) security | Mar. 31, 2022 USD ($) security Rate | Dec. 31, 2021 USD ($) security
Investments, Debt and Equity Securities [Abstract] |  |  |  |  |
Vertical risk retention interest | 5.00% |  | 5.00% | 5.00% |
Trading investments |  | $ 38,820 | $ 38,820 | $ 38,820 | $ 37,465
Number of available-for-sale securities with unrealized losses | security |  | 158 | 158 | 158 | 60
Number of available-for-sale securities | security |  | 186 | 186 | 186 | 180
Par value of mortgage-backed securities pledged to FRB |  | $ 720,000 | $ 720,000 | $ 720,000 | $ 888,000
Non-marketable securities investment |  | 69,000 | 69,000 | 69,000 | 69,000
Low income housing tax credit investments |  | 66,000 | 66,000 | 66,000 | 68,000
Low income housing tax credit investments, liability for unfunded commitments |  | 28,000 | $ 28,000 | $ 28,000 | 30,000
Low income housing tax credit investments, tax credits and benefits (current year less than) |  | $ 1,000 |  |  | $ 7,000
Low income housing tax credit investments, expected tax benefits recognized |  |  | 25.00% |  |

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- Definition Amount of affordable housing tax credits and other tax benefits recognized. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 323 -SubTopic 740 -Section 50 -Paragraph 2 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=116633289&loc=SL49122993-202985 + Details
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- Definition Amount of investment in qualified affordable housing projects. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 323 -SubTopic 740 -Section 50 -Paragraph 2 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=116633289&loc=SL49122993-202985 + Details
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