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v3.23.3

Securities, AFS Securities in Continuous Unrealized Loss Position (Details) $ in Thousands | Sep. 30, 2023 USD ($) Position | Dec. 31, 2022 USD ($) Position
--- | --- | ---
Unrealized Loss Position, Fair Value [Abstract] |  |
Less than 12 months | $ 6,379 | $ 509,788
12 months or longer | 1,390,772 | 1,012,964
Total | 1,397,151 | 1,522,752
Unrealized Loss Position, Unrealized Losses [Abstract] |  |
Less than 12 months | (160) | (36,681)
12 months or longer | (242,172) | (180,014)
Total | $ (242,332) | $ (216,695)
Unrealized Loss Position, Number of Positions [Abstract] |  |
Less than 12 months | Position | 33 | 245
12 months or longer | Position | 379 | 170
Total | Position | 412 | 415
AIR on AFS debt securities | $ 3,900 | $ 4,200
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 | $ 0 | $ 55,616
12 months or longer | 121,595 | 66,042
Total | 121,595 | 121,658
Unrealized Loss Position, Unrealized Losses [Abstract] |  |
Less than 12 months | 0 | (3,864)
12 months or longer | (11,565) | (7,369)
Total | $ (11,565) | $ (11,233)
Unrealized Loss Position, Number of Positions [Abstract] |  |
Less than 12 months | Position | 0 | 5
12 months or longer | Position | 8 | 3
Total | Position | 8 | 8
Federal Agency [Member] |  |
Unrealized Loss Position, Fair Value [Abstract] |  |
Less than 12 months | $ 0 | $ 0
12 months or longer | 203,756 | 206,419
Total | 203,756 | 206,419
Unrealized Loss Position, Unrealized Losses [Abstract] |  |
Less than 12 months | 0 | 0
12 months or longer | (44,636) | (42,000)
Total | $ (44,636) | $ (42,000)
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 | $ 747 | $ 3,679
12 months or longer | 82,538 | 78,395
Total | 83,285 | 82,074
Unrealized Loss Position, Unrealized Losses [Abstract] |  |
Less than 12 months | (21) | (341)
12 months or longer | (13,143) | (13,849)
Total | $ (13,164) | $ (14,190)
Unrealized Loss Position, Number of Positions [Abstract] |  |
Less than 12 months | Position | 1 | 2
12 months or longer | Position | 66 | 64
Total | Position | 67 | 66
Mortgage-Backed [Member] |  |
Unrealized Loss Position, Fair Value [Abstract] |  |
Less than 12 months | $ 463 | $ 204,447
12 months or longer | 414,686 | 267,926
Total | 415,149 | 472,373
Unrealized Loss Position, Unrealized Losses [Abstract] |  |
Less than 12 months | (7) | (15,048)
12 months or longer | (71,300) | (47,303)
Total | $ (71,307) | $ (62,351)
Unrealized Loss Position, Number of Positions [Abstract] |  |
Less than 12 months | Position | 25 | 149
12 months or longer | Position | 157 | 32
Total | Position | 182 | 181
Collateralized Mortgage Obligations [Member] |  |
Unrealized Loss Position, Fair Value [Abstract] |  |
Less than 12 months | $ 3,825 | $ 211,612
12 months or longer | 528,324 | 374,376
Total | 532,149 | 585,988
Unrealized Loss Position, Unrealized Losses [Abstract] |  |
Less than 12 months | (31) | (14,458)
12 months or longer | (94,414) | (66,299)
Total | $ (94,445) | $ (80,757)
Unrealized Loss Position, Number of Positions [Abstract] |  |
Less than 12 months | Position | 6 | 77
12 months or longer | Position | 118 | 49
Total | Position | 124 | 126
Corporate [Member] |  |
Unrealized Loss Position, Fair Value [Abstract] |  |
Less than 12 months | $ 1,344 | $ 34,434
12 months or longer | 39,873 | 19,806
Total | 41,217 | 54,240
Unrealized Loss Position, Unrealized Losses [Abstract] |  |
Less than 12 months | (101) | (2,970)
12 months or longer | (7,114) | (3,194)
Total | $ (7,215) | $ (6,164)
Unrealized Loss Position, Number of Positions [Abstract] |  |
Less than 12 months | Position | 1 | 12
12 months or longer | Position | 14 | 6
Total | Position | 15 | 18

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