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Investments - Narrative (Details) $ in Thousands | 3 Months Ended | 12 Months Ended
--- | --- | ---
Mar. 31, 2024 USD ($) security | Dec. 31, 2023 USD ($) security
Investments, Debt and Equity Securities [Abstract] |  |
Vertical risk retention interest | 5.00% |
Trading investments | $ 58,166 | $ 54,481
Number of government sponsored securities with unrealized losses | security | 228 | 213
Number of mortgage-backed securities | security | 258 | 248
Par value of mortgage-backed securities pledged to FRB | $ 578,000 | $ 612,000
Non-marketable securities investment | 14,000 | 14,000
Low income housing tax credit investments | 70,000 | 72,000
Liability for unfunded commitments | 23,000 | 30,000
Low income housing tax credit investments, tax credits and benefits (less than) | $ 1,000 | $ 11,000
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://www.xbrl.org/2003/role/recommendedDisclosureRef -Topic 323 -SubTopic 740 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org//1943274/2147481543/323-740-50-2 + Details
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