Securities - Continuous Unrealized Losses (Details) - USD ($) $ in Thousands	Sep. 30, 2023	Dec. 31, 2022
Schedule of Available-for-sale Debt Securities
Available-for-sale debt securities, Less than 12 Months, Fair Value	$ 382,537	$ 1,451,466
Available-for-sale debt securities, Gross Unrealized Loss, Less than 12 Months	(2,011)	(104,682)
Available-for-sale debt securities, 12 Months or More, Fair Value	5,327,754	4,332,275
Available-for-sale debt securities, Gross Unrealized Loss, 12 Months or More	(934,621)	(740,048)
Available-for-sale debt securities fair value, Total	5,710,291	5,783,741
Available-for-sale debt securities, Gross Unrealized Loss, Total	(936,632)	(844,730)
U.S. Treasury securities
Schedule of Available-for-sale Debt Securities
Available-for-sale debt securities, Less than 12 Months, Fair Value	0	131,843
Available-for-sale debt securities, Gross Unrealized Loss, Less than 12 Months	0	(8,761)
Available-for-sale debt securities, 12 Months or More, Fair Value	605,730	474,360
Available-for-sale debt securities, Gross Unrealized Loss, 12 Months or More	(70,562)	(61,342)
Available-for-sale debt securities fair value, Total	605,730	606,203
Available-for-sale debt securities, Gross Unrealized Loss, Total	(70,562)	(70,103)
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	199,139	97,403
Available-for-sale debt securities, Gross Unrealized Loss, Less than 12 Months	(861)	(6,902)
Available-for-sale debt securities, 12 Months or More, Fair Value	248,325	214,136
Available-for-sale debt securities, Gross Unrealized Loss, 12 Months or More	(64,387)	(49,364)
Available-for-sale debt securities fair value, Total	447,464	311,539
Available-for-sale debt securities, Gross Unrealized Loss, Total	(65,248)	(56,266)
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	4,434	252,144
Available-for-sale debt securities, Gross Unrealized Loss, Less than 12 Months	(96)	(30,029)
Available-for-sale debt securities, 12 Months or More, Fair Value	457,898	248,125
Available-for-sale debt securities, Gross Unrealized Loss, 12 Months or More	(82,658)	(47,094)
Available-for-sale debt securities fair value, Total	462,332	500,269
Available-for-sale debt securities, Gross Unrealized Loss, Total	(82,754)	(77,123)
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	63,660	307,536
Available-for-sale debt securities, Gross Unrealized Loss, Less than 12 Months	(517)	(20,346)
Available-for-sale debt securities, 12 Months or More, Fair Value	1,627,451	1,448,658
Available-for-sale debt securities, Gross Unrealized Loss, 12 Months or More	(288,440)	(228,554)
Available-for-sale debt securities fair value, Total	1,691,111	1,756,194
Available-for-sale debt securities, Gross Unrealized Loss, Total	(288,957)	(248,900)
Municipal securities
Schedule of Available-for-sale Debt Securities
Available-for-sale debt securities, Less than 12 Months, Fair Value	5,891	95,655
Available-for-sale debt securities, Gross Unrealized Loss, Less than 12 Months	(288)	(10,194)
Available-for-sale debt securities, 12 Months or More, Fair Value	237,665	159,439
Available-for-sale debt securities, Gross Unrealized Loss, 12 Months or More	(57,564)	(36,594)
Available-for-sale debt securities fair value, Total	243,556	255,094
Available-for-sale debt securities, Gross Unrealized Loss, Total	(57,852)	(46,788)
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	106,184
Available-for-sale debt securities, Gross Unrealized Loss, Less than 12 Months	0	(3,309)
Available-for-sale debt securities, 12 Months or More, Fair Value	365,320	282,301
Available-for-sale debt securities, Gross Unrealized Loss, 12 Months or More	(53,131)	(46,087)
Available-for-sale debt securities fair value, Total	365,320	388,485
Available-for-sale debt securities, Gross Unrealized Loss, Total	(53,131)	(49,396)
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	22,715
Available-for-sale debt securities, Gross Unrealized Loss, Less than 12 Months	0	(1,546)
Available-for-sale debt securities, 12 Months or More, Fair Value	570,787	626,509
Available-for-sale debt securities, Gross Unrealized Loss, 12 Months or More	(116,887)	(111,432)
Available-for-sale debt securities fair value, Total	570,787	649,224
Available-for-sale debt securities, Gross Unrealized Loss, Total	(116,887)	(112,978)
Corporate debt securities
Schedule of Available-for-sale Debt Securities
Available-for-sale debt securities, Less than 12 Months, Fair Value	0	173,595
Available-for-sale debt securities, Gross Unrealized Loss, Less than 12 Months	0	(17,907)
Available-for-sale debt securities, 12 Months or More, Fair Value	475,434	352,679
Available-for-sale debt securities, Gross Unrealized Loss, 12 Months or More	(178,067)	(129,321)
Available-for-sale debt securities fair value, Total	475,434	526,274
Available-for-sale debt securities, Gross Unrealized Loss, Total	(178,067)	(147,228)
Foreign government bonds
Schedule of Available-for-sale Debt Securities
Available-for-sale debt securities, Less than 12 Months, Fair Value	109,413	107,576
Available-for-sale debt securities, Gross Unrealized Loss, Less than 12 Months	(249)	(429)
Available-for-sale debt securities, 12 Months or More, Fair Value	85,433	36,143
Available-for-sale debt securities, Gross Unrealized Loss, 12 Months or More	(14,567)	(13,857)
Available-for-sale debt securities fair value, Total	194,846	143,719
Available-for-sale debt securities, Gross Unrealized Loss, Total	(14,816)	(14,286)
Asset-backed securities
Schedule of Available-for-sale Debt Securities
Available-for-sale debt securities, Less than 12 Months, Fair Value	0	12,450
Available-for-sale debt securities, Gross Unrealized Loss, Less than 12 Months	0	(524)
Available-for-sale debt securities, 12 Months or More, Fair Value	43,757	36,626
Available-for-sale debt securities, Gross Unrealized Loss, 12 Months or More	(1,062)	(1,552)
Available-for-sale debt securities fair value, Total	43,757	49,076
Available-for-sale debt securities, Gross Unrealized Loss, Total	(1,062)	(2,076)
Collateralized loan obligations (“CLOs”)
Schedule of Available-for-sale Debt Securities
Available-for-sale debt securities, Less than 12 Months, Fair Value	0	144,365
Available-for-sale debt securities, Gross Unrealized Loss, Less than 12 Months	0	(4,735)
Available-for-sale debt securities, 12 Months or More, Fair Value	609,954	453,299
Available-for-sale debt securities, Gross Unrealized Loss, 12 Months or More	(7,296)	(14,851)
Available-for-sale debt securities fair value, Total	609,954	597,664
Available-for-sale debt securities, Gross Unrealized Loss, Total	$ (7,296)	$ (19,586)