Securities (Continuous Unrealized Losses) (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Debt Securities, Available-for-sale [Line Items]
Available-for-sale debt securities, Less than 12 Months, Fair Value	$ 5,932,965	$ 1,519,603
Available-for-sale debt securities, Gross Unrealized Loss, Less than 12 Months	(106,229)	(15,456)
Available-for-sale debt securities, More than 12 Months, Fair Value	1,778,987	342,859
Available-for-sale debt securities, Gross Unrealized Loss, More than 12 Months	(66,622)	(7,005)
Available-for-sale debt securities, Fair Value, Total	7,711,952	1,862,462
Available-for-sale debt securities, Gross Unrealized Loss, Total	(172,851)	(22,461)
U.S. Treasury securities
Debt Securities, Available-for-sale [Line Items]
Available-for-sale debt securities, Less than 12 Months, Fair Value	935,776	352,521
Available-for-sale debt securities, Gross Unrealized Loss, Less than 12 Months	(14,689)	(1,260)
Available-for-sale debt securities, More than 12 Months, Fair Value	47,881	0
Available-for-sale debt securities, Gross Unrealized Loss, More than 12 Months	(1,998)	0
Available-for-sale debt securities, Fair Value, Total	983,657	352,521
Available-for-sale debt securities, Gross Unrealized Loss, Total	(16,687)	(1,260)
U.S. government agency and U.S. government-sponsored enterprise debt securities
Debt Securities, Available-for-sale [Line Items]
Available-for-sale debt securities, Less than 12 Months, Fair Value	773,647
Available-for-sale debt securities, Gross Unrealized Loss, Less than 12 Months	(18,000)
Available-for-sale debt securities, More than 12 Months, Fair Value	402,907
Available-for-sale debt securities, Gross Unrealized Loss, More than 12 Months	(16,710)
Available-for-sale debt securities, Fair Value, Total	1,176,554
Available-for-sale debt securities, Gross Unrealized Loss, Total	(34,710)
US government agencies And U.S. government-sponsored enterprise mortgage-backed securities - Commercial mortgage-backed securities
Debt Securities, Available-for-sale [Line Items]
Available-for-sale debt securities, Less than 12 Months, Fair Value	440,734	292,596
Available-for-sale debt securities, Gross Unrealized Loss, Less than 12 Months	(13,589)	(5,656)
Available-for-sale debt securities, More than 12 Months, Fair Value	257,745	3,543
Available-for-sale debt securities, Gross Unrealized Loss, More than 12 Months	(15,265)	(54)
Available-for-sale debt securities, Fair Value, Total	698,479	296,139
Available-for-sale debt securities, Gross Unrealized Loss, Total	(28,854)	(5,710)
US government agencies And U.S. government-sponsored enterprise mortgage-backed securities - Residential mortgage-backed securities
Debt Securities, Available-for-sale [Line Items]
Available-for-sale debt securities, Less than 12 Months, Fair Value	2,138,542	342,561
Available-for-sale debt securities, Gross Unrealized Loss, Less than 12 Months	(37,691)	(1,611)
Available-for-sale debt securities, More than 12 Months, Fair Value	330,522	0
Available-for-sale debt securities, Gross Unrealized Loss, More than 12 Months	(11,444)	0
Available-for-sale debt securities, Fair Value, Total	2,469,064	342,561
Available-for-sale debt securities, Gross Unrealized Loss, Total	(49,135)	(1,611)
Municipal securities
Debt Securities, Available-for-sale [Line Items]
Available-for-sale debt securities, Less than 12 Months, Fair Value	177,065	24,529
Available-for-sale debt securities, Gross Unrealized Loss, Less than 12 Months	(5,682)	(88)
Available-for-sale debt securities, More than 12 Months, Fair Value	17,003	0
Available-for-sale debt securities, Gross Unrealized Loss, More than 12 Months	(606)	0
Available-for-sale debt securities, Fair Value, Total	194,068	24,529
Available-for-sale debt securities, Gross Unrealized Loss, Total	(6,288)	(88)
Non-agency commercial mortgage-backed Securities
Debt Securities, Available-for-sale [Line Items]
Available-for-sale debt securities, Less than 12 Months, Fair Value	301,925	58,738
Available-for-sale debt securities, Gross Unrealized Loss, Less than 12 Months	(4,158)	(1,230)
Available-for-sale debt securities, More than 12 Months, Fair Value	40,013	7,920
Available-for-sale debt securities, Gross Unrealized Loss, More than 12 Months	(1,319)	0
Available-for-sale debt securities, Fair Value, Total	341,938	66,658
Available-for-sale debt securities, Gross Unrealized Loss, Total	(5,477)	(1,230)
Non-agency residential mortgage-backed Securities
Debt Securities, Available-for-sale [Line Items]
Available-for-sale debt securities, Less than 12 Months, Fair Value	707,792	90,156
Available-for-sale debt securities, Gross Unrealized Loss, Less than 12 Months	(8,966)	(506)
Available-for-sale debt securities, More than 12 Months, Fair Value	6,431	0
Available-for-sale debt securities, Gross Unrealized Loss, More than 12 Months	(11)	0
Available-for-sale debt securities, Fair Value, Total	714,223	90,156
Available-for-sale debt securities, Gross Unrealized Loss, Total	(8,977)	(506)
Corporate debt securities
Debt Securities, Available-for-sale [Line Items]
Available-for-sale debt securities, Less than 12 Months, Fair Value	183,916	251,674
Available-for-sale debt securities, Gross Unrealized Loss, Less than 12 Months	(3,084)	(3,645)
Available-for-sale debt securities, More than 12 Months, Fair Value	251,494	9,798
Available-for-sale debt securities, Gross Unrealized Loss, More than 12 Months	(13,505)	(203)
Available-for-sale debt securities, Fair Value, Total	435,410	261,472
Available-for-sale debt securities, Gross Unrealized Loss, Total	(16,589)	(3,848)
Foreign government bonds
Debt Securities, Available-for-sale [Line Items]
Available-for-sale debt securities, Less than 12 Months, Fair Value	27,097	106,828
Available-for-sale debt securities, Gross Unrealized Loss, Less than 12 Months	(5)	(1,460)
Available-for-sale debt securities, More than 12 Months, Fair Value	133,279	0
Available-for-sale debt securities, Gross Unrealized Loss, More than 12 Months	(3,476)	0
Available-for-sale debt securities, Fair Value, Total	160,376	106,828
Available-for-sale debt securities, Gross Unrealized Loss, Total	(3,481)	(1,460)
Asset-backed securities
Debt Securities, Available-for-sale [Line Items]
Available-for-sale debt securities, Less than 12 Months, Fair Value	24,885	0
Available-for-sale debt securities, Gross Unrealized Loss, Less than 12 Months	(301)	0
Available-for-sale debt securities, More than 12 Months, Fair Value	0	34,104
Available-for-sale debt securities, Gross Unrealized Loss, More than 12 Months	0	(242)
Available-for-sale debt securities, Fair Value, Total	24,885	34,104
Available-for-sale debt securities, Gross Unrealized Loss, Total	(301)	(242)
Collateralized loan obligations (“CLOs”)
Debt Securities, Available-for-sale [Line Items]
Available-for-sale debt securities, Less than 12 Months, Fair Value	221,586	0
Available-for-sale debt securities, Gross Unrealized Loss, Less than 12 Months	(64)	0
Available-for-sale debt securities, More than 12 Months, Fair Value	291,712	287,494
Available-for-sale debt securities, Gross Unrealized Loss, More than 12 Months	(2,288)	(6,506)
Available-for-sale debt securities, Fair Value, Total	513,298	287,494
Available-for-sale debt securities, Gross Unrealized Loss, Total	$ (2,352)	$ (6,506)

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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