Securities (Continuous Unrealized Losses) (Details) - USD ($) $ in Thousands	Jun. 30, 2021	Dec. 31, 2020
Schedule of Available-for-sale Debt Securities
Available-for-sale debt securities, Less than 12 Months, Fair Value	$ 4,169,504	$ 1,519,603
Available-for-sale debt securities, Gross Unrealized Loss, Less than 12 Months	(80,246)	(15,456)
Available-for-sale debt securities, 12 Months or More, Fair Value	509,227	342,859
Available-for-sale debt securities, Gross Unrealized Loss, 12 Months or More	(8,545)	(7,005)
Available-for-sale debt securities fair value, Total	4,678,731	1,862,462
Available-for-sale debt securities, Gross Unrealized Loss, Total	(88,791)	(22,461)
U.S. Treasury securities
Schedule of Available-for-sale Debt Securities
Available-for-sale debt securities, Less than 12 Months, Fair Value	544,599	352,521
Available-for-sale debt securities, Gross Unrealized Loss, Less than 12 Months	(6,098)	(1,260)
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	544,599	352,521
Available-for-sale debt securities, Gross Unrealized Loss, Total	(6,098)	(1,260)
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	782,327
Available-for-sale debt securities, Gross Unrealized Loss, Less than 12 Months	(17,402)
Available-for-sale debt securities, 12 Months or More, Fair Value	23,776
Available-for-sale debt securities, Gross Unrealized Loss, 12 Months or More	(1,200)
Available-for-sale debt securities fair value, Total	806,103
Available-for-sale debt securities, Gross Unrealized Loss, Total	(18,602)
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	491,515	292,596
Available-for-sale debt securities, Gross Unrealized Loss, Less than 12 Months	(11,487)	(5,656)
Available-for-sale debt securities, 12 Months or More, Fair Value	28,399	3,543
Available-for-sale debt securities, Gross Unrealized Loss, 12 Months or More	(1,196)	(54)
Available-for-sale debt securities fair value, Total	519,914	296,139
Available-for-sale debt securities, Gross Unrealized Loss, Total	(12,683)	(5,710)
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	1,346,061	342,561
Available-for-sale debt securities, Gross Unrealized Loss, Less than 12 Months	(25,170)	(1,611)
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	1,346,061	342,561
Available-for-sale debt securities, Gross Unrealized Loss, Total	(25,170)	(1,611)
Municipal securities
Schedule of Available-for-sale Debt Securities
Available-for-sale debt securities, Less than 12 Months, Fair Value	108,695	24,529
Available-for-sale debt securities, Gross Unrealized Loss, Less than 12 Months	(1,637)	(88)
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	108,695	24,529
Available-for-sale debt securities, Gross Unrealized Loss, Total	(1,637)	(88)
Non-agency commercial mortgage-backed securities
Schedule of Available-for-sale Debt Securities
Available-for-sale debt securities, Less than 12 Months, Fair Value	102,043	58,738
Available-for-sale debt securities, Gross Unrealized Loss, Less than 12 Months	(1,806)	(1,230)
Available-for-sale debt securities, 12 Months or More, Fair Value	15,579	7,920
Available-for-sale debt securities, Gross Unrealized Loss, 12 Months or More	(8)	0
Available-for-sale debt securities fair value, Total	117,622	66,658
Available-for-sale debt securities, Gross Unrealized Loss, Total	(1,814)	(1,230)
Non-agency residential mortgage-backed securities
Schedule of Available-for-sale Debt Securities
Available-for-sale debt securities, Less than 12 Months, Fair Value	464,404	90,156
Available-for-sale debt securities, Gross Unrealized Loss, Less than 12 Months	(2,216)	(506)
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	464,404	90,156
Available-for-sale debt securities, Gross Unrealized Loss, Total	(2,216)	(506)
Corporate debt securities
Schedule of Available-for-sale Debt Securities
Available-for-sale debt securities, Less than 12 Months, Fair Value	254,723	251,674
Available-for-sale debt securities, Gross Unrealized Loss, Less than 12 Months	(11,277)	(3,645)
Available-for-sale debt securities, 12 Months or More, Fair Value	57,100	9,798
Available-for-sale debt securities, Gross Unrealized Loss, 12 Months or More	(2,900)	(203)
Available-for-sale debt securities fair value, Total	311,823	261,472
Available-for-sale debt securities, Gross Unrealized Loss, Total	(14,177)	(3,848)
Foreign government bonds
Schedule of Available-for-sale Debt Securities
Available-for-sale debt securities, Less than 12 Months, Fair Value	59,189	106,828
Available-for-sale debt securities, Gross Unrealized Loss, Less than 12 Months	(3,146)	(1,460)
Available-for-sale debt securities, 12 Months or More, Fair Value	92,844	0
Available-for-sale debt securities, Gross Unrealized Loss, 12 Months or More	(770)	0
Available-for-sale debt securities fair value, Total	152,033	106,828
Available-for-sale debt securities, Gross Unrealized Loss, Total	(3,916)	(1,460)
Asset-backed securities
Schedule of Available-for-sale Debt Securities
Available-for-sale debt securities, Less than 12 Months, Fair Value	15,948	0
Available-for-sale debt securities, Gross Unrealized Loss, Less than 12 Months	(7)	0
Available-for-sale debt securities, 12 Months or More, Fair Value	0	34,104
Available-for-sale debt securities, Gross Unrealized Loss, 12 Months or More	0	(242)
Available-for-sale debt securities fair value, Total	15,948	34,104
Available-for-sale debt securities, Gross Unrealized Loss, Total	(7)	(242)
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	291,529	287,494
Available-for-sale debt securities, Gross Unrealized Loss, 12 Months or More	(2,471)	(6,506)
Available-for-sale debt securities fair value, Total	291,529	287,494
Available-for-sale debt securities, Gross Unrealized Loss, Total	$ (2,471)	$ (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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