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Investments - Narrative (Details) $ in Thousands | 3 Months Ended | 12 Months Ended
--- | --- | ---
Dec. 31, 2022 USD ($) security | Sep. 30, 2022 USD ($) | Jun. 30, 2021 USD ($) | Dec. 31, 2022 USD ($) security | Dec. 31, 2021 USD ($) security | Dec. 31, 2020 USD ($)
Investments, Debt and Equity Securities [Abstract] |  |  |  |  |  |
Vertical risk retention interest |  |  |  | 5.00% |  |
Increase in trading investments |  | $ 5,000 |  | $ 5,117 | $ 0 | $ 0
Trading investments | $ 55,903 |  |  | $ 55,903 | $ 37,465 |
Number of government sponsored securities with unrealized losses | security | 191 |  |  | 191 | 60 |
Number of mortgage-backed securities | security | 194 |  |  | 194 | 180 |
Par value of mortgage-backed securities pledged to FRB | $ 547,000 |  |  | $ 547,000 | $ 888,000 |
Gain (loss) on non-marketable securities investment | (60,000) |  | $ 35,000 |  |  |
Non-marketable securities investment | 8,000 |  |  | 8,000 | 69,000 |
Low income housing tax credit investments |  |  |  | 9,000 | 7,000 | 6,000
Amount of amortization reported in income tax expense |  |  |  | 7,000 | 6,000 | $ 5,000
Total carrying value of LIHTC investments | 80,000 |  |  | 80,000 | 68,000 |
Liability for unfunded commitments | $ 46,000 |  |  | $ 46,000 | $ 30,000 |

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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 https://asc.fasb.org/extlink&oid=116633289&loc=SL49122993-202985 + Details
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