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v3.23.1

Securities, AFS Securities in Continuous Unrealized Loss Position (Details) $ in Thousands | Mar. 31, 2023 USD ($) Position | Dec. 31, 2022 USD ($) Position
--- | --- | ---
Unrealized Loss Position, Fair Value [Abstract] |  |
Less than 12 months | $ 121,858 | $ 509,788
12 months or longer | 1,385,108 | 1,012,964
Total | 1,506,966 | 1,522,752
Unrealized Loss Position, Unrealized Losses [Abstract] |  |
Less than 12 months | (3,718) | (36,681)
12 months or longer | (192,273) | (180,014)
Total | $ (195,991) | $ (216,695)
Unrealized Loss Position, Number of Positions [Abstract] |  |
Less than 12 months | Position | 62 | 245
12 months or longer | Position | 332 | 170
Total | Position | 394 | 415
AIR on AFS debt securities | $ 4,100 | $ 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 | $ 9,818 | $ 55,616
12 months or longer | 113,761 | 66,042
Total | 123,579 | 121,658
Unrealized Loss Position, Unrealized Losses [Abstract] |  |
Less than 12 months | (114) | (3,864)
12 months or longer | (9,185) | (7,369)
Total | $ (9,299) | $ (11,233)
Unrealized Loss Position, Number of Positions [Abstract] |  |
Less than 12 months | Position | 1 | 5
12 months or longer | Position | 7 | 3
Total | Position | 8 | 8
Federal Agency [Member] |  |
Unrealized Loss Position, Fair Value [Abstract] |  |
Less than 12 months | $ 0 | $ 0
12 months or longer | 210,220 | 206,419
Total | 210,220 | 206,419
Unrealized Loss Position, Unrealized Losses [Abstract] |  |
Less than 12 months | 0 | 0
12 months or longer | (38,190) | (42,000)
Total | $ (38,190) | $ (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 | $ 1,454 | $ 3,679
12 months or longer | 82,792 | 78,395
Total | 84,246 | 82,074
Unrealized Loss Position, Unrealized Losses [Abstract] |  |
Less than 12 months | (51) | (341)
12 months or longer | (11,774) | (13,849)
Total | $ (11,825) | $ (14,190)
Unrealized Loss Position, Number of Positions [Abstract] |  |
Less than 12 months | Position | 1 | 2
12 months or longer | Position | 65 | 64
Total | Position | 66 | 66
Mortgage-Backed [Member] |  |
Unrealized Loss Position, Fair Value [Abstract] |  |
Less than 12 months | $ 22,278 | $ 204,447
12 months or longer | 440,057 | 267,926
Total | 462,335 | 472,373
Unrealized Loss Position, Unrealized Losses [Abstract] |  |
Less than 12 months | (736) | (15,048)
12 months or longer | (54,485) | (47,303)
Total | $ (55,221) | $ (62,351)
Unrealized Loss Position, Number of Positions [Abstract] |  |
Less than 12 months | Position | 33 | 149
12 months or longer | Position | 134 | 32
Total | Position | 167 | 181
Collateralized Mortgage Obligations [Member] |  |
Unrealized Loss Position, Fair Value [Abstract] |  |
Less than 12 months | $ 74,631 | $ 211,612
12 months or longer | 504,718 | 374,376
Total | 579,349 | 585,988
Unrealized Loss Position, Unrealized Losses [Abstract] |  |
Less than 12 months | (2,080) | (14,458)
12 months or longer | (71,199) | (66,299)
Total | $ (73,279) | $ (80,757)
Unrealized Loss Position, Number of Positions [Abstract] |  |
Less than 12 months | Position | 23 | 77
12 months or longer | Position | 97 | 49
Total | Position | 120 | 126
Corporate [Member] |  |
Unrealized Loss Position, Fair Value [Abstract] |  |
Less than 12 months | $ 13,677 | $ 34,434
12 months or longer | 33,560 | 19,806
Total | 47,237 | 54,240
Unrealized Loss Position, Unrealized Losses [Abstract] |  |
Less than 12 months | (737) | (2,970)
12 months or longer | (7,440) | (3,194)
Total | $ (8,177) | $ (6,164)
Unrealized Loss Position, Number of Positions [Abstract] |  |
Less than 12 months | Position | 4 | 12
12 months or longer | Position | 13 | 6
Total | Position | 17 | 18

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