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Securities - Securities with gross unrealized losses (Details) - USD ($) $ in Thousands | Mar. 31, 2025 | Dec. 31, 2024
--- | --- | ---
Securities Held to Maturity, Gross Unrealized Losses |  |
Twelve Months or More | $ 375,507 | $ 420,143
Securities Held to Maturity, Fair Value |  |
Twelve Months or More | 1,820,473 | 1,834,527
Securities Available for Sale, Gross Unrealized Losses |  |
Less Than Twelve Months | 3,032 | 2,594
Twelve Months or More | 515,042 | 806,730
Securities Available for Sale, Fair Value |  |
Less Than Twelve Months | 1,394,582 | 93,830
Twelve Months or More | 2,753,248 | 4,113,658
U.S. Treasuries |  |
Securities Available for Sale, Gross Unrealized Losses |  |
Less Than Twelve Months | 1 |
Securities Available for Sale, Fair Value |  |
Less Than Twelve Months | 18,294 |
U.S. Government agencies |  |
Securities Held to Maturity, Gross Unrealized Losses |  |
Twelve Months or More | 20,361 | 23,498
Securities Held to Maturity, Fair Value |  |
Twelve Months or More | 112,547 | 123,774
Securities Available for Sale, Gross Unrealized Losses |  |
Twelve Months or More |  | 18,789
Securities Available for Sale, Fair Value |  |
Twelve Months or More |  | 150,418
Residential mortgage-backed securities issued by U.S. government agencies or sponsored enterprises |  |
Securities Held to Maturity, Gross Unrealized Losses |  |
Twelve Months or More | 214,924 | 241,204
Securities Held to Maturity, Fair Value |  |
Twelve Months or More | 1,047,852 | 1,056,339
Securities Available for Sale, Gross Unrealized Losses |  |
Less Than Twelve Months | 1,037 | 294
Twelve Months or More | 168,622 | 282,129
Securities Available for Sale, Fair Value |  |
Less Than Twelve Months | 158,905 | 14,341
Twelve Months or More | 863,252 | 1,350,268
Residential collateralized mortgage-obligations issued by U.S. government agencies or sponsored enterprises |  |
Securities Held to Maturity, Gross Unrealized Losses |  |
Twelve Months or More | 63,798 | 72,057
Securities Held to Maturity, Fair Value |  |
Twelve Months or More | 341,205 | 339,664
Securities Available for Sale, Gross Unrealized Losses |  |
Less Than Twelve Months | 1,294 |
Twelve Months or More | 56,462 | 98,212
Securities Available for Sale, Fair Value |  |
Less Than Twelve Months | 908,932 |
Twelve Months or More | 318,887 | 454,908
Commercial mortgage-backed securities issued by U.S. government agencies or sponsored enterprises |  |
Securities Held to Maturity, Gross Unrealized Losses |  |
Twelve Months or More | 66,345 | 72,391
Securities Held to Maturity, Fair Value |  |
Twelve Months or More | 279,738 | 275,947
Securities Available for Sale, Gross Unrealized Losses |  |
Less Than Twelve Months | 224 | 792
Twelve Months or More | 84,022 | 193,788
Securities Available for Sale, Fair Value |  |
Less Than Twelve Months | 26,921 | 53,342
Twelve Months or More | 417,171 | 918,338
State and municipal obligations |  |
Securities Available for Sale, Gross Unrealized Losses |  |
Less Than Twelve Months | 100 | 1,484
Twelve Months or More | 175,164 | 170,125
Securities Available for Sale, Fair Value |  |
Less Than Twelve Months | 3,487 | 19,400
Twelve Months or More | 899,151 | 923,431
Small Business Administration loan-backed securities |  |
Securities Held to Maturity, Gross Unrealized Losses |  |
Twelve Months or More | 10,079 | 10,993
Securities Held to Maturity, Fair Value |  |
Twelve Months or More | 39,131 | 38,803
Securities Available for Sale, Gross Unrealized Losses |  |
Less Than Twelve Months | 376 | 24
Twelve Months or More | 29,264 | 41,697
Securities Available for Sale, Fair Value |  |
Less Than Twelve Months | 278,043 | 6,747
Twelve Months or More | 227,796 | 289,786
Corporate securities |  |
Securities Available for Sale, Gross Unrealized Losses |  |
Twelve Months or More | 1,508 | 1,990
Securities Available for Sale, Fair Value |  |
Twelve Months or More | $ 26,991 | $ 26,509

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