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Investments - Narrative (Details) $ in Thousands | 3 Months Ended | 12 Months Ended |
--- | --- | --- | ---
Dec. 31, 2022 USD ($) security | Jun. 30, 2021 USD ($) | Dec. 31, 2023 USD ($) security | Dec. 31, 2022 USD ($) security | Dec. 31, 2021 USD ($) | Mar. 31, 2023 USD ($)
Debt Securities, Available-for-sale [Line Items] |  |  |  |  |  |
Vertical risk retention interest |  |  | 5.00% | 5.00% |  |
Increase in trading investments |  |  | $ 0 | $ 5,117 | $ 0 |
Trading investments | $ 55,903 |  | $ 54,481 | $ 55,903 |  |
Number of government sponsored securities with unrealized losses | security | 191 |  | 213 | 191 |  |
Number of mortgage-backed securities | security | 194 |  | 248 | 194 |  |
Par value of mortgage-backed securities pledged to FRB | $ 547,000 |  | $ 612,000 | $ 547,000 |  |
Gain (loss) on non-marketable securities investment | (60,000) | $ 35,000 |  |  |  |
Non-marketable securities investment | 8,000 |  | 14,000 | 8,000 |  |
Low income housing tax credit investments |  |  | 11,000 | 9,000 | 7,000 |
Amount of amortization reported in income tax expense |  |  | 9,000 | 7,000 | $ 6,000 |
Total carrying value of LIHTC investments | 80,000 |  | 72,000 | 80,000 |  |
Liability for unfunded commitments | $ 46,000 |  | $ 30,000 | $ 46,000 |  |
Equity Securities |  |  |  |  |  |
Debt Securities, Available-for-sale [Line Items] |  |  |  |  |  |
Non-marketable securities investment |  |  |  |  |  | $ 5,000

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