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Securities, AFS Securities in Continuous Unrealized Loss Position (Details) $ in Thousands | Jun. 30, 2024 USD ($) Position | Dec. 31, 2023 USD ($) Position
--- | --- | ---
Unrealized Loss Position, Fair Value [Abstract] |  |
Less than 12 months | $ 33,951 | $ 2,765
12 months or longer | 1,357,437 | 1,422,826
Total | 1,391,388 | 1,425,591
Unrealized Loss Position, Unrealized Losses [Abstract] |  |
Less than 12 months | (156) | (82)
12 months or longer | (187,886) | (184,185)
Total | $ (188,042) | $ (184,267)
Unrealized Loss Position, Number of Positions [Abstract] |  |
Less than 12 months | Position | 12 | 10
12 months or longer | Position | 380 | 378
Total | Position | 392 | 388
AIR on AFS debt securities | $ 4,000 | $ 3,900
Debt Securities, Available-for-Sale, Accrued Interest, after Allowance for Credit Loss, Statement of Financial Position [Extensible Enumeration] | Other Assets | Other Assets
U.S. Treasury [Member] |  |
Unrealized Loss Position, Fair Value [Abstract] |  |
Less than 12 months | $ 4,976 | $ 0
12 months or longer | 115,324 | 125,024
Total | 120,300 | 125,024
Unrealized Loss Position, Unrealized Losses [Abstract] |  |
Less than 12 months | (6) | 0
12 months or longer | (8,260) | (8,278)
Total | $ (8,266) | $ (8,278)
Unrealized Loss Position, Number of Positions [Abstract] |  |
Less than 12 months | Position | 1 | 0
12 months or longer | Position | 7 | 8
Total | Position | 8 | 8
Federal Agency [Member] |  |
Unrealized Loss Position, Fair Value [Abstract] |  |
Less than 12 months | $ 0 | $ 0
12 months or longer | 214,326 | 214,740
Total | 214,326 | 214,740
Unrealized Loss Position, Unrealized Losses [Abstract] |  |
Less than 12 months | 0 | 0
12 months or longer | (34,040) | (33,644)
Total | $ (34,040) | $ (33,644)
Unrealized Loss Position, Number of Positions [Abstract] |  |
Less than 12 months | Position | 0 | 0
12 months or longer | Position | 16 | 16
Total | Position | 16 | 16
State & Municipal [Member] |  |
Unrealized Loss Position, Fair Value [Abstract] |  |
Less than 12 months | $ 758 | $ 0
12 months or longer | 85,244 | 85,528
Total | 86,002 | 85,528
Unrealized Loss Position, Unrealized Losses [Abstract] |  |
Less than 12 months | (7) | 0
12 months or longer | (9,847) | (9,956)
Total | $ (9,854) | $ (9,956)
Unrealized Loss Position, Number of Positions [Abstract] |  |
Less than 12 months | Position | 1 | 0
12 months or longer | Position | 66 | 66
Total | Position | 67 | 66
Mortgage-Backed [Member] |  |
Unrealized Loss Position, Fair Value [Abstract] |  |
Less than 12 months | $ 284 | $ 53
12 months or longer | 391,446 | 421,259
Total | 391,730 | 421,312
Unrealized Loss Position, Unrealized Losses [Abstract] |  |
Less than 12 months | (3) | (1)
12 months or longer | (53,286) | (51,565)
Total | $ (53,289) | $ (51,566)
Unrealized Loss Position, Number of Positions [Abstract] |  |
Less than 12 months | Position | 6 | 7
12 months or longer | Position | 157 | 156
Total | Position | 163 | 163
Collateralized Mortgage Obligations [Member] |  |
Unrealized Loss Position, Fair Value [Abstract] |  |
Less than 12 months | $ 26,485 | $ 1,333
12 months or longer | 510,558 | 536,678
Total | 537,043 | 538,011
Unrealized Loss Position, Unrealized Losses [Abstract] |  |
Less than 12 months | (118) | (6)
12 months or longer | (76,001) | (73,351)
Total | $ (76,119) | $ (73,357)
Unrealized Loss Position, Number of Positions [Abstract] |  |
Less than 12 months | Position | 3 | 2
12 months or longer | Position | 120 | 118
Total | Position | 123 | 120
Corporate [Member] |  |
Unrealized Loss Position, Fair Value [Abstract] |  |
Less than 12 months | $ 1,448 | $ 1,379
12 months or longer | 40,539 | 39,597
Total | 41,987 | 40,976
Unrealized Loss Position, Unrealized Losses [Abstract] |  |
Less than 12 months | (22) | (75)
12 months or longer | (6,452) | (7,391)
Total | $ (6,474) | $ (7,466)
Unrealized Loss Position, Number of Positions [Abstract] |  |
Less than 12 months | Position | 1 | 1
12 months or longer | Position | 14 | 14
Total | Position | 15 | 15

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