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Tax Credit Equity Investments (Details) - USD ($) | 3 Months Ended |
--- | --- | ---
Mar. 31, 2024 | Mar. 31, 2023 | Dec. 31, 2023
Schedule of Equity Method Investments [Line Items] |  |  |
Decrease in Retained earnings | $ (977,195,000) |  | $ (959,604,000)
Decrease in other assets | (290,698,000) |  | (270,475,000)
Tax credit investment balances | 44,400,000 |  |
Unfunded commitments | 7,200,000 |  |
Amortization expense | 800,000 |  |
Tax credit | 800,000 |  |
Other tax benefits | 100,000 |  |
Impairment losses | $ 0 |  |
Amortization |  | $ 500,000 |
Low income housing, tax credits |  | 500,000 |
Low income housing partnerships and other investments |  | $ 3,100,000 |
Cumulative Effect, Period of Adoption, Adjustment | Accounting Standards Update 2023-02 |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |
Decrease in Retained earnings |  |  | 1,000,000
Decrease in other assets |  |  | $ 1,000,000

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