Securities (Summary of Gross Unrealized Losses and Fair Value of Debt Securities Available-for-Sale with Unrealized Losses) (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Debt Securities, Available-for-sale [Line Items]
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	$ 3,195,732	$ 880,507
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	(43,236)	(6,453)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	383,754	18,597
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	(14,645)	(815)
Debt Securities, Available-for-sale, Unrealized Loss Position, Total	3,579,486	899,104
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss, Total	57,881	7,268
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	2,292,062	575,329
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	(30,777)	(3,728)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	176,946	18,527
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	(7,315)	(815)
Debt Securities, Available-for-sale, Unrealized Loss Position, Total	2,469,008	593,856
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss, Total	38,092	4,543
Asset-backed Securities
Debt Securities, Available-for-sale [Line Items]
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	195,708	143,764
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	(4,823)	(2,076)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	117,751	70
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	(4,968)	0
Debt Securities, Available-for-sale, Unrealized Loss Position, Total	313,459	143,834
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss, Total	9,791	2,076
State and Municipal Securities
Debt Securities, Available-for-sale [Line Items]
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	237,354	86,471
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	(3,862)	(592)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	40,343	0
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	(1,076)	0
Debt Securities, Available-for-sale, Unrealized Loss Position, Total	277,697	86,471
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss, Total	4,938	592
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	100,813	74,943
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	(1,988)	(57)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	48,714	0
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	(1,286)	0
Debt Securities, Available-for-sale, Unrealized Loss Position, Total	149,527	74,943
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss, Total	3,274	$ 57
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	212,259
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	(955)
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, Total	212,259
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss, Total	955
US Government Securities
Debt Securities, Available-for-sale [Line Items]
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	157,536
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	(831)
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, Total	157,536
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss, Total	$ 831

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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