Investment Securities (Details 2) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Debt Securities, Available-for-sale, Unrealized Loss Position	$ 5,424,991	$ 547,636
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	5,102,495	457,559
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	(63,559)	(2,474)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	(322,496)	(90,077)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	(8,535)	(904)
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss	(72,095)	(3,378)
Government agency and government-sponsored enterprise pass through securities [Member]
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss	(9,213)	(37)
US States and Political Subdivisions Debt Securities [Member]
Debt Securities, Available-for-sale, Unrealized Loss Position	534,806	5,919
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	505,080	5,919
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	(6,965)	(18)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	(29,726)	0
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	(1,008)	0
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss	(7,973)	(18)
Commercial Mortgage Backed Securities [Member]
Debt Securities, Available-for-sale, Unrealized Loss Position	547,683	58,408
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	440,938	58,408
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	(5,066)	(37)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	(106,745)	0
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	(4,147)	0
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss	(9,213)	(37)
Government agency and government-sponsored enterprise collateralized mortgage obligations [Member]
Debt Securities, Available-for-sale, Unrealized Loss Position	283,785	97,863
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	216,445	97,863
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	(3,757)	(280)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	(67,340)	0
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	(2,113)	0
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss	(5,870)	(280)
US Treasury Securities [Member]
Debt Securities, Available-for-sale, Unrealized Loss Position	628,767
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	628,767
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	(8,298)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	0
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	0
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss	(8,298)	0
Corporate Debt Securities [Member]
Debt Securities, Available-for-sale, Unrealized Loss Position	32,761	87,596
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	32,761	87,596
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	(757)	(404)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	0	0
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	0	0
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss	(757)	(404)
Mortgage-backed Securities, Issued by Private Enterprises
Debt Securities, Available-for-sale, Unrealized Loss Position	397,619	3,058
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	397,619	3,058
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	(3,244)	(10)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	0	0
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	0	0
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss	(3,244)	(10)
Collateralized Loan Obligations [Member]
Debt Securities, Available-for-sale, Unrealized Loss Position	181,349	125,414
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	137,619	96,442
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	(374)	(729)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	(43,730)	(28,972)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	(70)	(195)
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss	(444)	(924)
Private Label Collateralized Mortgage Obligations [Member]
Debt Securities, Available-for-sale, Unrealized Loss Position	201,988	862
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	201,988	788
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	(3,291)	(19)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	0	(74)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	0	(2)
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss	(3,291)	(21)
Asset-backed Securities [Member]
Debt Securities, Available-for-sale, Unrealized Loss Position	54,504	75,667
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	38,742	14,636
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	(137)	(53)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	(15,762)	(61,031)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	(187)	(707)
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss	(324)	(760)
SBA asset-backed securities [Member]
Debt Securities, Available-for-sale, Unrealized Loss Position	1,864	2,127
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	0	2,127
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	0	(27)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	(1,864)	0
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	(31)	0
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss	(32)	(27)
Residential Mortgage Backed Securities [Member]
Debt Securities, Available-for-sale, Unrealized Loss Position	2,559,865	90,722
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	2,502,536	90,722
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	(31,670)	(897)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	(57,329)	0
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	(979)	0
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss	$ (32,649)	$ (897)

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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