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Securities - Schedule of Debt Securities, Available-for-Sale, Unrealized Loss Position, Fair Value (Details) - USD ($) $ in Thousands | Mar. 31, 2025 | Dec. 31, 2024
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Schedule of Available-for-sale Debt Securities |  |
Available-for-sale debt securities, Less than 12 Months, Fair Value | $ 3,190,731 | $ 2,735,499
Available-for-sale debt securities, Gross Unrealized Loss, Less than 12 Months | (10,670) | (16,861)
Available-for-sale debt securities, 12 Months or More, Fair Value | 4,358,452 | 4,413,878
Available-for-sale debt securities, Gross Unrealized Loss, 12 Months or More | (594,259) | (657,376)
Available-for-sale debt securities fair value, Total | 7,549,183 | 7,149,377
Available-for-sale debt securities, Gross Unrealized Loss, Total | (604,929) | (674,237)
U.S. Treasury securities |  |
Schedule of Available-for-sale Debt Securities |  |
Available-for-sale debt securities, Less than 12 Months, Fair Value | 0 | 0
Available-for-sale debt securities, Gross Unrealized Loss, Less than 12 Months | 0 | 0
Available-for-sale debt securities, 12 Months or More, Fair Value | 610,981 | 638,265
Available-for-sale debt securities, Gross Unrealized Loss, 12 Months or More | (30,310) | (38,035)
Available-for-sale debt securities fair value, Total | 610,981 | 638,265
Available-for-sale debt securities, Gross Unrealized Loss, Total | (30,310) | (38,035)
U.S. government agency and U.S. government-sponsored enterprise debt securities |  |
Schedule of Available-for-sale Debt Securities |  |
Available-for-sale debt securities, Less than 12 Months, Fair Value | 0 | 0
Available-for-sale debt securities, Gross Unrealized Loss, Less than 12 Months | 0 | 0
Available-for-sale debt securities, 12 Months or More, Fair Value | 268,406 | 262,587
Available-for-sale debt securities, Gross Unrealized Loss, 12 Months or More | (38,022) | (45,633)
Available-for-sale debt securities fair value, Total | 268,406 | 262,587
Available-for-sale debt securities, Gross Unrealized Loss, Total | (38,022) | (45,633)
U.S. government agency and U.S. government-sponsored enterprise mortgage-backed securities - Commercial mortgage-backed securities |  |
Schedule of Available-for-sale Debt Securities |  |
Available-for-sale debt securities, Less than 12 Months, Fair Value | 2,476 | 2,741
Available-for-sale debt securities, Gross Unrealized Loss, Less than 12 Months | (25) | (30)
Available-for-sale debt securities, 12 Months or More, Fair Value | 358,728 | 377,756
Available-for-sale debt securities, Gross Unrealized Loss, 12 Months or More | (39,575) | (47,177)
Available-for-sale debt securities fair value, Total | 361,204 | 380,497
Available-for-sale debt securities, Gross Unrealized Loss, Total | (39,600) | (47,207)
U.S. government agency and U.S. government-sponsored enterprise mortgage-backed securities - Residential mortgage-backed securities |  |
Schedule of Available-for-sale Debt Securities |  |
Available-for-sale debt securities, Less than 12 Months, Fair Value | 3,179,008 | 2,719,228
Available-for-sale debt securities, Gross Unrealized Loss, Less than 12 Months | (10,604) | (16,404)
Available-for-sale debt securities, 12 Months or More, Fair Value | 1,524,704 | 1,528,252
Available-for-sale debt securities, Gross Unrealized Loss, 12 Months or More | (212,427) | (232,382)
Available-for-sale debt securities fair value, Total | 4,703,712 | 4,247,480
Available-for-sale debt securities, Gross Unrealized Loss, Total | (223,031) | (248,786)
Municipal securities |  |
Schedule of Available-for-sale Debt Securities |  |
Available-for-sale debt securities, Less than 12 Months, Fair Value | 4,814 | 2,763
Available-for-sale debt securities, Gross Unrealized Loss, Less than 12 Months | (40) | (95)
Available-for-sale debt securities, 12 Months or More, Fair Value | 241,040 | 245,360
Available-for-sale debt securities, Gross Unrealized Loss, 12 Months or More | (40,480) | (37,091)
Available-for-sale debt securities fair value, Total | 245,854 | 248,123
Available-for-sale debt securities, Gross Unrealized Loss, Total | (40,520) | (37,186)
Non-agency commercial mortgage-backed securities |  |
Schedule of Available-for-sale Debt Securities |  |
Available-for-sale debt securities, Less than 12 Months, Fair Value | 4,433 | 10,767
Available-for-sale debt securities, Gross Unrealized Loss, Less than 12 Months | (1) | (332)
Available-for-sale debt securities, 12 Months or More, Fair Value | 221,078 | 235,668
Available-for-sale debt securities, Gross Unrealized Loss, 12 Months or More | (32,313) | (35,435)
Available-for-sale debt securities fair value, Total | 225,511 | 246,435
Available-for-sale debt securities, Gross Unrealized Loss, Total | (32,314) | (35,767)
Non-agency residential mortgage-backed securities |  |
Schedule of Available-for-sale Debt Securities |  |
Available-for-sale debt securities, Less than 12 Months, Fair Value | 0 | 0
Available-for-sale debt securities, Gross Unrealized Loss, Less than 12 Months | 0 | 0
Available-for-sale debt securities, 12 Months or More, Fair Value | 430,068 | 433,608
Available-for-sale debt securities, Gross Unrealized Loss, 12 Months or More | (72,342) | (80,919)
Available-for-sale debt securities fair value, Total | 430,068 | 433,608
Available-for-sale debt securities, Gross Unrealized Loss, Total | (72,342) | (80,919)
Corporate debt securities |  |
Schedule of Available-for-sale Debt Securities |  |
Available-for-sale debt securities, Less than 12 Months, Fair Value | 0 | 0
Available-for-sale debt securities, Gross Unrealized Loss, Less than 12 Months | 0 | 0
Available-for-sale debt securities, 12 Months or More, Fair Value | 536,542 | 526,166
Available-for-sale debt securities, Gross Unrealized Loss, 12 Months or More | (116,958) | (127,334)
Available-for-sale debt securities fair value, Total | 536,542 | 526,166
Available-for-sale debt securities, Gross Unrealized Loss, Total | (116,958) | (127,334)
Foreign government bonds |  |
Schedule of Available-for-sale Debt Securities |  |
Available-for-sale debt securities, Less than 12 Months, Fair Value | 0 | 0
Available-for-sale debt securities, Gross Unrealized Loss, Less than 12 Months | 0 | 0
Available-for-sale debt securities, 12 Months or More, Fair Value | 88,747 | 87,008
Available-for-sale debt securities, Gross Unrealized Loss, 12 Months or More | (11,253) | (12,992)
Available-for-sale debt securities fair value, Total | 88,747 | 87,008
Available-for-sale debt securities, Gross Unrealized Loss, Total | (11,253) | (12,992)
Asset-backed securities |  |
Schedule of Available-for-sale Debt Securities |  |
Available-for-sale debt securities, Less than 12 Months, Fair Value | 0 | 0
Available-for-sale debt securities, Gross Unrealized Loss, Less than 12 Months | 0 | 0
Available-for-sale debt securities, 12 Months or More, Fair Value | 33,735 | 34,715
Available-for-sale debt securities, Gross Unrealized Loss, 12 Months or More | (502) | (371)
Available-for-sale debt securities fair value, Total | 33,735 | 34,715
Available-for-sale debt securities, Gross Unrealized Loss, Total | (502) | (371)
Collateralized loan obligations (“CLOs”) |  |
Schedule of Available-for-sale Debt Securities |  |
Available-for-sale debt securities, Less than 12 Months, Fair Value | 0 | 0
Available-for-sale debt securities, Gross Unrealized Loss, Less than 12 Months | 0 | 0
Available-for-sale debt securities, 12 Months or More, Fair Value | 44,423 | 44,493
Available-for-sale debt securities, Gross Unrealized Loss, 12 Months or More | (77) | (7)
Available-for-sale debt securities fair value, Total | 44,423 | 44,493
Available-for-sale debt securities, Gross Unrealized Loss, Total | (77) | $ (7)
US Treasury Securities, With No Unrealized Loss Position |  |
Schedule of Available-for-sale Debt Securities |  |
AFS debt securities | $ 320,000 |

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