Investment Securities - Schedule Of Investments Within The Available For Sale Portfolio That Had Unrealized Losses (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Unrealized Losses
Fair value, less than 12 months	$ 655,820	$ 960,053
Unrealized losses, less than 12 months	(3,616)	(15,826)
Fair value, 12 months or longer	553,979	3,112,632
Unrealized loss, 12 months or longer	(7,288)	(92,005)
Fair value, total	1,209,799	4,072,685
Unrealized losses, total	(10,904)	(107,831)
U.S. treasuries
Unrealized Losses
Fair value, less than 12 months	0	0
Unrealized losses, less than 12 months	0	0
Fair value, 12 months or longer	100	98
Unrealized loss, 12 months or longer	0	(2)
Fair value, total	100	98
Unrealized losses, total	0	(2)
Government agency issued mortgage-backed securities (“MBS”)
Unrealized Losses
Fair value, less than 12 months	174,983	597,008
Unrealized losses, less than 12 months	(495)	(12,335)
Fair value, 12 months or longer	192,755	1,537,106
Unrealized loss, 12 months or longer	(2,061)	(46,065)
Fair value, total	367,738	2,134,114
Unrealized losses, total	(2,556)	(58,400)
Government agency issued collateralized mortgage obligations (“CMO”)
Unrealized Losses
Fair value, less than 12 months	378,815	290,863
Unrealized losses, less than 12 months	(1,970)	(2,860)
Fair value, 12 months or longer	361,124	1,560,420
Unrealized loss, 12 months or longer	(5,227)	(45,821)
Fair value, total	739,939	1,851,283
Unrealized losses, total	(7,197)	(48,681)
Other U.S. government agencies
Unrealized Losses
Fair value, less than 12 months	98,471	29,776
Unrealized losses, less than 12 months	(1,121)	(73)
Fair value, 12 months or longer	0	0
Unrealized loss, 12 months or longer	0	0
Fair value, total	98,471	29,776
Unrealized losses, total	(1,121)	(73)
Corporates and other debt
Unrealized Losses
Fair value, less than 12 months		25,114
Unrealized losses, less than 12 months		(344)
Fair value, 12 months or longer		15,008
Unrealized loss, 12 months or longer		(117)
Fair value, total		40,122
Unrealized losses, total		(461)
State and municipalities
Unrealized Losses
Fair value, less than 12 months	3,551	17,292
Unrealized losses, less than 12 months	(30)	(214)
Fair value, 12 months or longer	0	0
Unrealized loss, 12 months or longer	0	0
Fair value, total	3,551	17,292
Unrealized losses, total	$ (30)	$ (214)

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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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