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Securities, AFS Securities in Continuous Unrealized Loss Position (Details) $ in Thousands | Mar. 31, 2022 USD ($) Position | Dec. 31, 2021 USD ($) Position
--- | --- | ---
Unrealized Loss Position, Fair Value [Abstract] |  |
Less than 12 months | $ 1,142,258 | $ 811,115
12 months or longer | 440,297 | 253,578
Total | 1,582,555 | 1,064,693
Unrealized Loss Position, Unrealized Losses [Abstract] |  |
Less than 12 months | (56,606) | (13,238)
12 months or longer | (42,735) | (8,704)
Total | $ (99,341) | $ (21,942)
Unrealized Loss Position, Number of Positions [Abstract] |  |
Less than 12 months | Position | 270 | 127
12 months or longer | Position | 51 | 22
Total | Position | 321 | 149
AIR on AFS debt securities | $ 4,000 | $ 3,900
U.S. Treasury [Member] |  |
Unrealized Loss Position, Fair Value [Abstract] |  |
Less than 12 months | 117,635 | 49,105
12 months or longer | 0 | 0
Total | 117,635 | 49,105
Unrealized Loss Position, Unrealized Losses [Abstract] |  |
Less than 12 months | (4,809) | (6)
12 months or longer | 0 | 0
Total | $ (4,809) | $ (6)
Unrealized Loss Position, Number of Positions [Abstract] |  |
Less than 12 months | Position | 7 | 2
12 months or longer | Position | 0 | 0
Total | Position | 7 | 2
Federal Agency [Member] |  |
Unrealized Loss Position, Fair Value [Abstract] |  |
Less than 12 months | $ 2,586 | $ 41,618
12 months or longer | 223,026 | 198,313
Total | 225,612 | 239,931
Unrealized Loss Position, Unrealized Losses [Abstract] |  |
Less than 12 months | (269) | (1,846)
12 months or longer | (22,564) | (6,677)
Total | $ (22,833) | $ (8,523)
Unrealized Loss Position, Number of Positions [Abstract] |  |
Less than 12 months | Position | 1 | 4
12 months or longer | Position | 15 | 12
Total | Position | 16 | 16
State & Municipal [Member] |  |
Unrealized Loss Position, Fair Value [Abstract] |  |
Less than 12 months | $ 74,201 | $ 87,515
12 months or longer | 14,097 | 0
Total | 88,298 | 87,515
Unrealized Loss Position, Unrealized Losses [Abstract] |  |
Less than 12 months | (5,690) | (1,559)
12 months or longer | (1,347) | 0
Total | $ (7,037) | $ (1,559)
Unrealized Loss Position, Number of Positions [Abstract] |  |
Less than 12 months | Position | 55 | 61
12 months or longer | Position | 10 | 0
Total | Position | 65 | 61
Mortgage-Backed [Member] |  |
Unrealized Loss Position, Fair Value [Abstract] |  |
Less than 12 months | $ 333,335 | $ 281,217
12 months or longer | 182,752 | 39,491
Total | 516,087 | 320,708
Unrealized Loss Position, Unrealized Losses [Abstract] |  |
Less than 12 months | (11,186) | (4,319)
12 months or longer | (17,177) | (1,525)
Total | $ (28,363) | $ (5,844)
Unrealized Loss Position, Number of Positions [Abstract] |  |
Less than 12 months | Position | 105 | 24
12 months or longer | Position | 19 | 6
Total | Position | 124 | 30
Collateralized Mortgage Obligations [Member] |  |
Unrealized Loss Position, Fair Value [Abstract] |  |
Less than 12 months | $ 569,994 | $ 341,673
12 months or longer | 20,422 | 15,774
Total | 590,416 | 357,447
Unrealized Loss Position, Unrealized Losses [Abstract] |  |
Less than 12 months | (33,158) | (5,495)
12 months or longer | (1,647) | (502)
Total | $ (34,805) | $ (5,997)
Unrealized Loss Position, Number of Positions [Abstract] |  |
Less than 12 months | Position | 88 | 34
12 months or longer | Position | 7 | 4
Total | Position | 95 | 38
Corporate [Member] |  |
Unrealized Loss Position, Fair Value [Abstract] |  |
Less than 12 months | $ 44,507 | $ 9,987
12 months or longer | 0 | 0
Total | 44,507 | 9,987
Unrealized Loss Position, Unrealized Losses [Abstract] |  |
Less than 12 months | (1,494) | (13)
12 months or longer | 0 | 0
Total | $ (1,494) | $ (13)
Unrealized Loss Position, Number of Positions [Abstract] |  |
Less than 12 months | Position | 14 | 2
12 months or longer | Position | 0 | 0
Total | Position | 14 | 2

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