Securities - Schedule of Debt Securities, Available-for-Sale, Unrealized Loss Position, Fair Value (Details) - USD ($) $ in Thousands	Mar. 31, 2026	Dec. 31, 2025
Schedule of Available-for-sale Debt Securities
Available-for-sale debt securities, Less than 12 Months, Fair Value	$ 3,350,272	$ 1,375,852
Available-for-sale debt securities, Gross Unrealized Loss, Less than 12 Months	(37,510)	(7,107)
Available-for-sale debt securities, 12 Months or More, Fair Value	3,838,344	4,071,829
Available-for-sale debt securities, Gross Unrealized Loss, 12 Months or More	(469,651)	(468,528)
Available-for-sale debt securities fair value, Total	7,188,616	5,447,681
Available-for-sale debt securities, Gross Unrealized Loss, Total	(507,161)	(475,635)
U.S. Treasury securities
Schedule of Available-for-sale Debt Securities
Available-for-sale debt securities, Less than 12 Months, Fair Value	510,306	323,019
Available-for-sale debt securities, Gross Unrealized Loss, Less than 12 Months	(5,956)	(1,627)
Available-for-sale debt securities, 12 Months or More, Fair Value	577,595	575,638
Available-for-sale debt securities, Gross Unrealized Loss, 12 Months or More	(13,102)	(15,350)
Available-for-sale debt securities fair value, Total	1,087,901	898,657
Available-for-sale debt securities, Gross Unrealized Loss, Total	(19,058)	(16,977)
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	255,863	257,654
Available-for-sale debt securities, Gross Unrealized Loss, 12 Months or More	(31,640)	(30,033)
Available-for-sale debt securities fair value, Total	255,863	257,654
Available-for-sale debt securities, Gross Unrealized Loss, Total	(31,640)	(30,033)
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	3,512	0
Available-for-sale debt securities, Gross Unrealized Loss, Less than 12 Months	(57)	0
Available-for-sale debt securities, 12 Months or More, Fair Value	242,595	256,503
Available-for-sale debt securities, Gross Unrealized Loss, 12 Months or More	(27,302)	(27,312)
Available-for-sale debt securities fair value, Total	246,107	256,503
Available-for-sale debt securities, Gross Unrealized Loss, Total	(27,359)	(27,312)
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	2,834,504	1,052,833
Available-for-sale debt securities, Gross Unrealized Loss, Less than 12 Months	(31,455)	(5,480)
Available-for-sale debt securities, 12 Months or More, Fair Value	1,462,115	1,582,952
Available-for-sale debt securities, Gross Unrealized Loss, 12 Months or More	(182,051)	(182,169)
Available-for-sale debt securities fair value, Total	4,296,619	2,635,785
Available-for-sale debt securities, Gross Unrealized Loss, Total	(213,506)	(187,649)
Municipal securities
Schedule of Available-for-sale Debt Securities
Available-for-sale debt securities, Less than 12 Months, Fair Value	1,950	0
Available-for-sale debt securities, Gross Unrealized Loss, Less than 12 Months	(42)	0
Available-for-sale debt securities, 12 Months or More, Fair Value	233,125	237,214
Available-for-sale debt securities, Gross Unrealized Loss, 12 Months or More	(37,352)	(34,193)
Available-for-sale debt securities fair value, Total	235,075	237,214
Available-for-sale debt securities, Gross Unrealized Loss, Total	(37,394)	(34,193)
Non-agency commercial 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	174,870	190,948
Available-for-sale debt securities, Gross Unrealized Loss, 12 Months or More	(22,416)	(22,139)
Available-for-sale debt securities fair value, Total	174,870	190,948
Available-for-sale debt securities, Gross Unrealized Loss, Total	(22,416)	(22,139)
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	373,497	393,787
Available-for-sale debt securities, Gross Unrealized Loss, 12 Months or More	(58,349)	(58,421)
Available-for-sale debt securities fair value, Total	373,497	393,787
Available-for-sale debt securities, Gross Unrealized Loss, Total	(58,349)	(58,421)
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	447,583	454,975
Available-for-sale debt securities, Gross Unrealized Loss, 12 Months or More	(87,575)	(89,183)
Available-for-sale debt securities fair value, Total	447,583	454,975
Available-for-sale debt securities, Gross Unrealized Loss, Total	(87,575)	(89,183)
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	40,671	90,769
Available-for-sale debt securities, Gross Unrealized Loss, 12 Months or More	(9,329)	(9,231)
Available-for-sale debt securities fair value, Total	40,671	90,769
Available-for-sale debt securities, Gross Unrealized Loss, Total	(9,329)	(9,231)
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	30,430	31,389
Available-for-sale debt securities, Gross Unrealized Loss, 12 Months or More	(535)	(497)
Available-for-sale debt securities fair value, Total	30,430	31,389
Available-for-sale debt securities, Gross Unrealized Loss, Total	$ (535)	$ (497)

Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in continuous unrealized loss position for more than 12 months, without allowance for credit loss. Includes beneficial interest in securitized financial asset.

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