Securities (Continuous Unrealized Losses) (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Schedule of Available-for-sale Debt Securities
Available-for-sale debt securities, Less than 12 Months, Fair Value	$ 1,506,992	$ 1,388,661
Available-for-sale debt securities, Gross Unrealized Loss, Less than 12 Months	(23,670)	(18,990)
Available-for-sale debt securities, 12 Months or More, Fair Value	90,974	351,048
Available-for-sale debt securities, Gross Unrealized Loss, 12 Months or More	(1,777)	(4,249)
Available-for-sale debt securities Fair Value, Total	1,597,966	1,739,709
Available-for-sale debt securities, Gross Unrealized Loss, Total	(25,447)	(23,239)
U.S. Treasury securities
Schedule of Available-for-sale Debt Securities
Available-for-sale debt securities, Less than 12 Months, Fair Value		0
Available-for-sale debt securities, Gross Unrealized Loss, Less than 12 Months		0
Available-for-sale debt securities, 12 Months or More, Fair Value		176,422
Available-for-sale debt securities, Gross Unrealized Loss, 12 Months or More		(793)
Available-for-sale debt securities Fair Value, Total		176,422
Available-for-sale debt securities, Gross Unrealized Loss, Total		(793)
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	336,399	310,349
Available-for-sale debt securities, Gross Unrealized Loss, Less than 12 Months	(2,410)	(4,407)
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	336,399	310,349
Available-for-sale debt securities, Gross Unrealized Loss, Total	(2,410)	(4,407)
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	224,593	204,675
Available-for-sale debt securities, Gross Unrealized Loss, Less than 12 Months	(4,194)	(2,346)
Available-for-sale debt securities, 12 Months or More, Fair Value	10,456	108,314
Available-for-sale debt securities, Gross Unrealized Loss, 12 Months or More	(67)	(2,548)
Available-for-sale debt securities Fair Value, Total	235,049	312,989
Available-for-sale debt securities, Gross Unrealized Loss, Total	(4,261)	(4,894)
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	62,150	325,354
Available-for-sale debt securities, Gross Unrealized Loss, Less than 12 Months	(1,057)	(1,234)
Available-for-sale debt securities, 12 Months or More, Fair Value	0	34,337
Available-for-sale debt securities, Gross Unrealized Loss, 12 Months or More	0	(243)
Available-for-sale debt securities Fair Value, Total	62,150	359,691
Available-for-sale debt securities, Gross Unrealized Loss, Total	(1,057)	(1,477)
Municipal securities
Schedule of Available-for-sale Debt Securities
Available-for-sale debt securities, Less than 12 Months, Fair Value	151,283	31,130
Available-for-sale debt securities, Gross Unrealized Loss, Less than 12 Months	(1,346)	(109)
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	151,283	31,130
Available-for-sale debt securities, Gross Unrealized Loss, Total	(1,346)	(109)
Non-agency commercial mortgage-backed securities
Schedule of Available-for-sale Debt Securities
Available-for-sale debt securities, Less than 12 Months, Fair Value	66,469	7,914
Available-for-sale debt securities, Gross Unrealized Loss, Less than 12 Months	(1,210)	(6)
Available-for-sale debt securities, 12 Months or More, Fair Value	7,907	0
Available-for-sale debt securities, Gross Unrealized Loss, 12 Months or More	(13)	0
Available-for-sale debt securities Fair Value, Total	74,376	7,914
Available-for-sale debt securities, Gross Unrealized Loss, Total	(1,223)	(6)
Non-agency residential mortgage-backed securities
Schedule of Available-for-sale Debt Securities
Available-for-sale debt securities, Less than 12 Months, Fair Value	135,192	42,894
Available-for-sale debt securities, Gross Unrealized Loss, Less than 12 Months	(475)	(285)
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	135,192	42,894
Available-for-sale debt securities, Gross Unrealized Loss, Total	(475)	(285)
Corporate debt securities
Schedule of Available-for-sale Debt Securities
Available-for-sale debt securities, Less than 12 Months, Fair Value	145,134	0
Available-for-sale debt securities, Gross Unrealized Loss, Less than 12 Months	(866)	0
Available-for-sale debt securities, 12 Months or More, Fair Value	9,463	9,888
Available-for-sale debt securities, Gross Unrealized Loss, 12 Months or More	(537)	(113)
Available-for-sale debt securities Fair Value, Total	154,597	9,888
Available-for-sale debt securities, Gross Unrealized Loss, Total	(1,403)	(113)
Foreign government bonds
Schedule of Available-for-sale Debt Securities
Available-for-sale debt securities, Less than 12 Months, Fair Value	102,350	129,074
Available-for-sale debt securities, Gross Unrealized Loss, Less than 12 Months	(1,534)	(407)
Available-for-sale debt securities, 12 Months or More, Fair Value	0	9,900
Available-for-sale debt securities, Gross Unrealized Loss, 12 Months or More	0	(100)
Available-for-sale debt securities Fair Value, Total	102,350	138,974
Available-for-sale debt securities, Gross Unrealized Loss, Total	(1,534)	(507)
Asset-backed securities
Schedule of Available-for-sale Debt Securities
Available-for-sale debt securities, Less than 12 Months, Fair Value	0	52,565
Available-for-sale debt securities, Gross Unrealized Loss, Less than 12 Months	0	(902)
Available-for-sale debt securities, 12 Months or More, Fair Value	63,148	12,187
Available-for-sale debt securities, Gross Unrealized Loss, 12 Months or More	(1,160)	(452)
Available-for-sale debt securities Fair Value, Total	63,148	64,752
Available-for-sale debt securities, Gross Unrealized Loss, Total	(1,160)	(1,354)
Collateralized loan obligations (“CLOs”)
Schedule of Available-for-sale Debt Securities
Available-for-sale debt securities, Less than 12 Months, Fair Value	283,422	284,706
Available-for-sale debt securities, Gross Unrealized Loss, Less than 12 Months	(10,578)	(9,294)
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	283,422	284,706
Available-for-sale debt securities, Gross Unrealized Loss, Total	$ (10,578)	$ (9,294)

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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