Securities - Continuous Unrealized Losses (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Debt Securities, Available-for-sale [Line Items]
Available-for-sale debt securities, Less than 12 Months, Fair Value	$ 1,451,466	$ 5,932,965
Available-for-sale debt securities, Gross Unrealized Loss, Less than 12 Months	(104,682)	(106,229)
Available-for-sale debt securities, More than 12 Months, Fair Value	4,332,275	1,778,987
Available-for-sale debt securities, Gross Unrealized Loss, More than 12 Months	(740,048)	(66,622)
Available-for-sale debt securities, Fair Value, Total	5,783,741	7,711,952
Available-for-sale debt securities, Gross Unrealized Loss, Total	(844,730)	(172,851)
U.S. Treasury securities
Debt Securities, Available-for-sale [Line Items]
Available-for-sale debt securities, Less than 12 Months, Fair Value	131,843	935,776
Available-for-sale debt securities, Gross Unrealized Loss, Less than 12 Months	(8,761)	(14,689)
Available-for-sale debt securities, More than 12 Months, Fair Value	474,360	47,881
Available-for-sale debt securities, Gross Unrealized Loss, More than 12 Months	(61,342)	(1,998)
Available-for-sale debt securities, Fair Value, Total	606,203	983,657
Available-for-sale debt securities, Gross Unrealized Loss, Total	(70,103)	(16,687)
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	97,403	773,647
Available-for-sale debt securities, Gross Unrealized Loss, Less than 12 Months	(6,902)	(18,000)
Available-for-sale debt securities, More than 12 Months, Fair Value	214,136	402,907
Available-for-sale debt securities, Gross Unrealized Loss, More than 12 Months	(49,364)	(16,710)
Available-for-sale debt securities, Fair Value, Total	311,539	1,176,554
Available-for-sale debt securities, Gross Unrealized Loss, Total	(56,266)	(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	252,144	440,734
Available-for-sale debt securities, Gross Unrealized Loss, Less than 12 Months	(30,029)	(13,589)
Available-for-sale debt securities, More than 12 Months, Fair Value	248,125	257,745
Available-for-sale debt securities, Gross Unrealized Loss, More than 12 Months	(47,094)	(15,265)
Available-for-sale debt securities, Fair Value, Total	500,269	698,479
Available-for-sale debt securities, Gross Unrealized Loss, Total	(77,123)	(28,854)
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	307,536	2,138,542
Available-for-sale debt securities, Gross Unrealized Loss, Less than 12 Months	(20,346)	(37,691)
Available-for-sale debt securities, More than 12 Months, Fair Value	1,448,658	330,522
Available-for-sale debt securities, Gross Unrealized Loss, More than 12 Months	(228,554)	(11,444)
Available-for-sale debt securities, Fair Value, Total	1,756,194	2,469,064
Available-for-sale debt securities, Gross Unrealized Loss, Total	(248,900)	(49,135)
Municipal securities:
Debt Securities, Available-for-sale [Line Items]
Available-for-sale debt securities, Less than 12 Months, Fair Value	95,655	177,065
Available-for-sale debt securities, Gross Unrealized Loss, Less than 12 Months	(10,194)	(5,682)
Available-for-sale debt securities, More than 12 Months, Fair Value	159,439	17,003
Available-for-sale debt securities, Gross Unrealized Loss, More than 12 Months	(36,594)	(606)
Available-for-sale debt securities, Fair Value, Total	255,094	194,068
Available-for-sale debt securities, Gross Unrealized Loss, Total	(46,788)	(6,288)
Non-agency commercial mortgage-backed Securities
Debt Securities, Available-for-sale [Line Items]
Available-for-sale debt securities, Less than 12 Months, Fair Value	106,184	301,925
Available-for-sale debt securities, Gross Unrealized Loss, Less than 12 Months	(3,309)	(4,158)
Available-for-sale debt securities, More than 12 Months, Fair Value	282,301	40,013
Available-for-sale debt securities, Gross Unrealized Loss, More than 12 Months	(46,087)	(1,319)
Available-for-sale debt securities, Fair Value, Total	388,485	341,938
Available-for-sale debt securities, Gross Unrealized Loss, Total	(49,396)	(5,477)
Non-agency residential mortgage-backed Securities
Debt Securities, Available-for-sale [Line Items]
Available-for-sale debt securities, Less than 12 Months, Fair Value	22,715	707,792
Available-for-sale debt securities, Gross Unrealized Loss, Less than 12 Months	(1,546)	(8,966)
Available-for-sale debt securities, More than 12 Months, Fair Value	626,509	6,431
Available-for-sale debt securities, Gross Unrealized Loss, More than 12 Months	(111,432)	(11)
Available-for-sale debt securities, Fair Value, Total	649,224	714,223
Available-for-sale debt securities, Gross Unrealized Loss, Total	(112,978)	(8,977)
Corporate debt securities
Debt Securities, Available-for-sale [Line Items]
Available-for-sale debt securities, Less than 12 Months, Fair Value	173,595	183,916
Available-for-sale debt securities, Gross Unrealized Loss, Less than 12 Months	(17,907)	(3,084)
Available-for-sale debt securities, More than 12 Months, Fair Value	352,679	251,494
Available-for-sale debt securities, Gross Unrealized Loss, More than 12 Months	(129,321)	(13,505)
Available-for-sale debt securities, Fair Value, Total	526,274	435,410
Available-for-sale debt securities, Gross Unrealized Loss, Total	(147,228)	(16,589)
Foreign government bonds
Debt Securities, Available-for-sale [Line Items]
Available-for-sale debt securities, Less than 12 Months, Fair Value	107,576	27,097
Available-for-sale debt securities, Gross Unrealized Loss, Less than 12 Months	(429)	(5)
Available-for-sale debt securities, More than 12 Months, Fair Value	36,143	133,279
Available-for-sale debt securities, Gross Unrealized Loss, More than 12 Months	(13,857)	(3,476)
Available-for-sale debt securities, Fair Value, Total	143,719	160,376
Available-for-sale debt securities, Gross Unrealized Loss, Total	(14,286)	(3,481)
Asset-backed securities
Debt Securities, Available-for-sale [Line Items]
Available-for-sale debt securities, Less than 12 Months, Fair Value	12,450	24,885
Available-for-sale debt securities, Gross Unrealized Loss, Less than 12 Months	(524)	(301)
Available-for-sale debt securities, More than 12 Months, Fair Value	36,626	0
Available-for-sale debt securities, Gross Unrealized Loss, More than 12 Months	(1,552)	0
Available-for-sale debt securities, Fair Value, Total	49,076	24,885
Available-for-sale debt securities, Gross Unrealized Loss, Total	(2,076)	(301)
Collateralized loan obligations (“CLOs”)
Debt Securities, Available-for-sale [Line Items]
Available-for-sale debt securities, Less than 12 Months, Fair Value	144,365	221,586
Available-for-sale debt securities, Gross Unrealized Loss, Less than 12 Months	(4,735)	(64)
Available-for-sale debt securities, More than 12 Months, Fair Value	453,299	291,712
Available-for-sale debt securities, Gross Unrealized Loss, More than 12 Months	(14,851)	(2,288)
Available-for-sale debt securities, Fair Value, Total	597,664	513,298
Available-for-sale debt securities, Gross Unrealized Loss, Total	$ (19,586)	$ (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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