Securities (Summary of Gross Unrealized Losses and Fair Value of Debt Securities Available-for-Sale with Unrealized Losses) (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Debt Securities, Available-for-sale [Line Items]
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	$ 1,202,775	$ 3,195,732
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	(85,581)	(43,236)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	3,328,941	383,754
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	(608,749)	(14,645)
Debt Securities, Available-for-sale, Unrealized Loss Position, Total	4,531,716	3,579,486
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss, Total	694,330	57,881
Asset-backed Securities
Debt Securities, Available-for-sale [Line Items]
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	76,877	195,708
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	(7,579)	(4,823)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	250,475	117,751
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	(41,404)	(4,968)
Debt Securities, Available-for-sale, Unrealized Loss Position, Total	327,352	313,459
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss, Total	48,983	9,791
State and Municipal Securities
Debt Securities, Available-for-sale [Line Items]
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	309,675	237,354
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	(23,690)	(3,862)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	485,620	40,343
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	(101,905)	(1,076)
Debt Securities, Available-for-sale, Unrealized Loss Position, Total	795,295	277,697
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss, Total	125,595	4,938
U.S. Government Agency and Government-Sponsored Enterprise Securities [Member]
Debt Securities, Available-for-sale [Line Items]
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	68,656	100,813
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	(1,375)	(1,988)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	139,364	48,714
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	(12,687)	(1,286)
Debt Securities, Available-for-sale, Unrealized Loss Position, Total	208,020	149,527
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss, Total	14,062	3,274
U.S. Government Agency and Government-Sponsored Enterprise Mortgage-Backed Securities and Collateralized Mortgage Obligations
Debt Securities, Available-for-sale [Line Items]
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	735,898	2,292,062
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	(50,201)	(30,777)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	2,005,957	176,946
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	(378,852)	(7,315)
Debt Securities, Available-for-sale, Unrealized Loss Position, Total	2,741,855	2,469,008
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss, Total	429,053	38,092
US Government Securities
Debt Securities, Available-for-sale [Line Items]
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	0	157,536
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	0	(831)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	167,896	0
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	(15,153)	0
Debt Securities, Available-for-sale, Unrealized Loss Position, Total	167,896	157,536
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss, Total	15,153	831
Non-agency collateralized mortgage obligations
Debt Securities, Available-for-sale [Line Items]
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	11,669	212,259
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	(2,736)	(955)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	279,629	0
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	(58,748)	0
Debt Securities, Available-for-sale, Unrealized Loss Position, Total	291,298	212,259
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss, Total	$ 61,484	$ 955

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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