Securities - Continuous Unrealized Losses (Details) - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023
Schedule of Available-for-sale Debt Securities
Available-for-sale debt securities, Less than 12 Months, Fair Value	$ 1,600,117	$ 125,924
Available-for-sale debt securities, Gross Unrealized Loss, Less than 12 Months	(4,571)	(721)
Available-for-sale debt securities, 12 Months or More, Fair Value	4,900,507	5,532,528
Available-for-sale debt securities, Gross Unrealized Loss, 12 Months or More	(731,907)	(728,216)
Available-for-sale debt securities fair value, Total	6,500,624	5,658,452
Available-for-sale debt securities, Gross Unrealized Loss, Total	(736,478)	(728,937)
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	621,094	623,978
Available-for-sale debt securities, Gross Unrealized Loss, 12 Months or More	(55,196)	(52,313)
Available-for-sale debt securities fair value, Total	621,094	623,978
Available-for-sale debt securities, Gross Unrealized Loss, Total	(55,196)	(52,313)
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	360,802	364,446
Available-for-sale debt securities, Gross Unrealized Loss, 12 Months or More	(49,874)	(47,640)
Available-for-sale debt securities fair value, Total	360,802	364,446
Available-for-sale debt securities, Gross Unrealized Loss, Total	(49,874)	(47,640)
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	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	450,965	463,572
Available-for-sale debt securities, Gross Unrealized Loss, 12 Months or More	(57,669)	(63,276)
Available-for-sale debt securities fair value, Total	450,965	463,572
Available-for-sale debt securities, Gross Unrealized Loss, Total	(57,669)	(63,276)
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	1,577,361	9,402
Available-for-sale debt securities, Gross Unrealized Loss, Less than 12 Months	(4,504)	(558)
Available-for-sale debt securities, 12 Months or More, Fair Value	1,642,455	1,661,112
Available-for-sale debt securities, Gross Unrealized Loss, 12 Months or More	(236,858)	(229,155)
Available-for-sale debt securities fair value, Total	3,219,816	1,670,514
Available-for-sale debt securities, Gross Unrealized Loss, Total	(241,362)	(229,713)
Municipal securities
Schedule of Available-for-sale Debt Securities
Available-for-sale debt securities, Less than 12 Months, Fair Value	4,189	2,825
Available-for-sale debt securities, Gross Unrealized Loss, Less than 12 Months	(6)	(15)
Available-for-sale debt securities, 12 Months or More, Fair Value	252,268	254,773
Available-for-sale debt securities, Gross Unrealized Loss, 12 Months or More	(37,906)	(36,327)
Available-for-sale debt securities fair value, Total	256,457	257,598
Available-for-sale debt securities, Gross Unrealized Loss, Total	(37,912)	(36,342)
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	2,742
Available-for-sale debt securities, Gross Unrealized Loss, Less than 12 Months	0	(4)
Available-for-sale debt securities, 12 Months or More, Fair Value	333,996	364,774
Available-for-sale debt securities, Gross Unrealized Loss, 12 Months or More	(39,838)	(42,058)
Available-for-sale debt securities fair value, Total	333,996	367,516
Available-for-sale debt securities, Gross Unrealized Loss, Total	(39,838)	(42,062)
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	519,657	553,671
Available-for-sale debt securities, Gross Unrealized Loss, 12 Months or More	(90,048)	(89,664)
Available-for-sale debt securities fair value, Total	519,657	553,671
Available-for-sale debt securities, Gross Unrealized Loss, Total	(90,048)	(89,664)
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	502,647	502,425
Available-for-sale debt securities, Gross Unrealized Loss, 12 Months or More	(150,854)	(151,076)
Available-for-sale debt securities fair value, Total	502,647	502,425
Available-for-sale debt securities, Gross Unrealized Loss, Total	(150,854)	(151,076)
Foreign government bonds
Schedule of Available-for-sale Debt Securities
Available-for-sale debt securities, Less than 12 Months, Fair Value	18,567	110,955
Available-for-sale debt securities, Gross Unrealized Loss, Less than 12 Months	(61)	(144)
Available-for-sale debt securities, 12 Months or More, Fair Value	88,060	88,616
Available-for-sale debt securities, Gross Unrealized Loss, 12 Months or More	(11,940)	(11,384)
Available-for-sale debt securities fair value, Total	106,627	199,571
Available-for-sale debt securities, Gross Unrealized Loss, Total	(12,001)	(11,528)
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	40,712	42,300
Available-for-sale debt securities, Gross Unrealized Loss, 12 Months or More	(575)	(934)
Available-for-sale debt securities fair value, Total	40,712	42,300
Available-for-sale debt securities, Gross Unrealized Loss, Total	(575)	(934)
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	87,851	612,861
Available-for-sale debt securities, Gross Unrealized Loss, 12 Months or More	(1,149)	(4,389)
Available-for-sale debt securities fair value, Total	87,851	612,861
Available-for-sale debt securities, Gross Unrealized Loss, Total	$ (1,149)	$ (4,389)