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Investment Tax Credits (Tables) | 12 Months Ended
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Dec. 31, 2023
Federal Home Loan Banks [Abstract] |
Affordable Housing Tax Credit Investments, Other Tax Credit Investments, and Related Unfunded Commitments [Table Text Block] | The following table presents the Company's tax credit investments, which consisted entirely of affordable housing tax credit investments and related unfunded capital commitments as of December 31, 2023 and 2022:
(in thousands) | December 31, 2023 |  | December 31, 2022
Other Assets: |  |  |
Affordable housing tax credit investments | $ | 210,873 |  |  | $ | 143,719 |
Other Liabilities: |  |  |
Unfunded affordable housing tax credit commitments | $ | 114,082 |  |  | $ | 81,632 |
Affordable Housing Tax Credit Investments [Table Text Block] | The following table presents other information relating to the Company's affordable housing tax credit investments for the years ended December 31, 2023, 2022, and 2021:
(in thousands) | 2023 |  | 2022 |  | 2021
Proportional amortization | 16,777 |  |  | 12,026 |  |  | 10,003 |
Tax credit investment credits and tax benefits | 20,932 |  |  | 14,553 |  |  | 12,253 |

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