Securities (Continuous Unrealized Losses) (Details) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Schedule of Available-for-sale Debt Securities
Available-for-sale debt securities, Less than 12 Months, Fair Value	$ 4,834,798	$ 5,932,965
Available-for-sale debt securities, Gross Unrealized Loss, Less than 12 Months	(244,058)	(106,229)
Available-for-sale debt securities, 12 Months or More, Fair Value	1,428,558	1,778,987
Available-for-sale debt securities, Gross Unrealized Loss, 12 Months or More	(124,338)	(66,622)
Available-for-sale debt securities fair value, Total	6,263,356	7,711,952
Available-for-sale debt securities, Gross Unrealized Loss, Total	(368,396)	(172,851)
U.S. Treasury securities
Schedule of Available-for-sale Debt Securities
Available-for-sale debt securities, Less than 12 Months, Fair Value	452,031	935,776
Available-for-sale debt securities, Gross Unrealized Loss, Less than 12 Months	(23,354)	(14,689)
Available-for-sale debt securities, 12 Months or More, Fair Value	162,785	47,881
Available-for-sale debt securities, Gross Unrealized Loss, 12 Months or More	(15,066)	(1,998)
Available-for-sale debt securities fair value, Total	614,816	983,657
Available-for-sale debt securities, Gross Unrealized Loss, Total	(38,420)	(16,687)
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	283,790	773,647
Available-for-sale debt securities, Gross Unrealized Loss, Less than 12 Months	(21,418)	(18,000)
Available-for-sale debt securities, 12 Months or More, Fair Value	13,639	402,907
Available-for-sale debt securities, Gross Unrealized Loss, 12 Months or More	(861)	(16,710)
Available-for-sale debt securities fair value, Total	297,429	1,176,554
Available-for-sale debt securities, Gross Unrealized Loss, Total	(22,279)	(34,710)
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	428,714	440,734
Available-for-sale debt securities, Gross Unrealized Loss, Less than 12 Months	(22,960)	(13,589)
Available-for-sale debt securities, 12 Months or More, Fair Value	94,653	257,745
Available-for-sale debt securities, Gross Unrealized Loss, 12 Months or More	(10,562)	(15,265)
Available-for-sale debt securities fair value, Total	523,367	698,479
Available-for-sale debt securities, Gross Unrealized Loss, Total	(33,522)	(28,854)
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	1,651,592	2,138,542
Available-for-sale debt securities, Gross Unrealized Loss, Less than 12 Months	(77,331)	(37,691)
Available-for-sale debt securities, 12 Months or More, Fair Value	363,817	330,522
Available-for-sale debt securities, Gross Unrealized Loss, 12 Months or More	(35,538)	(11,444)
Available-for-sale debt securities fair value, Total	2,015,409	2,469,064
Available-for-sale debt securities, Gross Unrealized Loss, Total	(112,869)	(49,135)
Municipal securities
Schedule of Available-for-sale Debt Securities
Available-for-sale debt securities, Less than 12 Months, Fair Value	243,211	177,065
Available-for-sale debt securities, Gross Unrealized Loss, Less than 12 Months	(20,042)	(5,682)
Available-for-sale debt securities, 12 Months or More, Fair Value	0	17,003
Available-for-sale debt securities, Gross Unrealized Loss, 12 Months or More	0	(606)
Available-for-sale debt securities fair value, Total	243,211	194,068
Available-for-sale debt securities, Gross Unrealized Loss, Total	(20,042)	(6,288)
Non-agency commercial mortgage-backed securities
Schedule of Available-for-sale Debt Securities
Available-for-sale debt securities, Less than 12 Months, Fair Value	360,543	301,925
Available-for-sale debt securities, Gross Unrealized Loss, Less than 12 Months	(17,424)	(4,158)
Available-for-sale debt securities, 12 Months or More, Fair Value	67,676	40,013
Available-for-sale debt securities, Gross Unrealized Loss, 12 Months or More	(6,101)	(1,319)
Available-for-sale debt securities fair value, Total	428,219	341,938
Available-for-sale debt securities, Gross Unrealized Loss, Total	(23,525)	(5,477)
Non-agency residential mortgage-backed securities
Schedule of Available-for-sale Debt Securities
Available-for-sale debt securities, Less than 12 Months, Fair Value	724,439	707,792
Available-for-sale debt securities, Gross Unrealized Loss, Less than 12 Months	(42,033)	(8,966)
Available-for-sale debt securities, 12 Months or More, Fair Value	81,681	6,431
Available-for-sale debt securities, Gross Unrealized Loss, 12 Months or More	(6,694)	(11)
Available-for-sale debt securities fair value, Total	806,120	714,223
Available-for-sale debt securities, Gross Unrealized Loss, Total	(48,727)	(8,977)
Corporate debt securities
Schedule of Available-for-sale Debt Securities
Available-for-sale debt securities, Less than 12 Months, Fair Value	279,491	183,916
Available-for-sale debt securities, Gross Unrealized Loss, Less than 12 Months	(16,008)	(3,084)
Available-for-sale debt securities, 12 Months or More, Fair Value	275,912	251,494
Available-for-sale debt securities, Gross Unrealized Loss, 12 Months or More	(39,089)	(13,505)
Available-for-sale debt securities fair value, Total	555,403	435,410
Available-for-sale debt securities, Gross Unrealized Loss, Total	(55,097)	(16,589)
Foreign government bonds
Schedule of Available-for-sale Debt Securities
Available-for-sale debt securities, Less than 12 Months, Fair Value	19,022	27,097
Available-for-sale debt securities, Gross Unrealized Loss, Less than 12 Months	(43)	(5)
Available-for-sale debt securities, 12 Months or More, Fair Value	77,195	133,279
Available-for-sale debt securities, Gross Unrealized Loss, 12 Months or More	(7,627)	(3,476)
Available-for-sale debt securities fair value, Total	96,217	160,376
Available-for-sale debt securities, Gross Unrealized Loss, Total	(7,670)	(3,481)
Asset-backed securities
Schedule of Available-for-sale Debt Securities
Available-for-sale debt securities, Less than 12 Months, Fair Value	71,362	24,885
Available-for-sale debt securities, Gross Unrealized Loss, Less than 12 Months	(798)	(301)
Available-for-sale debt securities, 12 Months or More, Fair Value	0	0
Available-for-sale debt securities, Gross Unrealized Loss, 12 Months or More	0	0
Available-for-sale debt securities fair value, Total	71,362	24,885
Available-for-sale debt securities, Gross Unrealized Loss, Total	(798)	(301)
Collateralized loan obligations (“CLOs”)
Schedule of Available-for-sale Debt Securities
Available-for-sale debt securities, Less than 12 Months, Fair Value	320,603	221,586
Available-for-sale debt securities, Gross Unrealized Loss, Less than 12 Months	(2,647)	(64)
Available-for-sale debt securities, 12 Months or More, Fair Value	291,200	291,712
Available-for-sale debt securities, Gross Unrealized Loss, 12 Months or More	(2,800)	(2,288)
Available-for-sale debt securities fair value, Total	611,803	513,298
Available-for-sale debt securities, Gross Unrealized Loss, Total	$ (5,447)	$ (2,352)

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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