Securities (Summary of Gross Unrealized Losses and Fair Value of the Investments with Unrealized Losses) (Details) - USD ($) $ in Thousands	Sep. 30, 2022	Dec. 31, 2021
Debt Securities, Available-for-sale [Line Items]
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	$ 2,290,709	$ 3,195,732
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	293,439	43,236
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	2,366,825	383,754
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	453,896	14,645
Debt Securities, Available-for-sale, Unrealized Loss Position	4,657,534	3,579,486
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss	747,335	57,881
U.S. Government Agency and Government-Sponsored Enterprise Mortgage-Backed Securities and Collateralized Mortgage Obligations [Member]
Debt Securities, Available-for-sale [Line Items]
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	1,071,973	2,292,062
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	106,441	30,777
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	1,757,493	176,946
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	346,237	7,315
Debt Securities, Available-for-sale, Unrealized Loss Position	2,829,466	2,469,008
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss	452,678	38,092
Asset-backed Securities [Member]
Debt Securities, Available-for-sale [Line Items]
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	129,541	195,708
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	14,741	4,823
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	204,467	117,751
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	35,900	4,968
Debt Securities, Available-for-sale, Unrealized Loss Position	334,008	313,459
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss	50,641	9,791
State and Municipal Securities [Member]
Debt Securities, Available-for-sale [Line Items]
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	601,998	237,354
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	99,002	3,862
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	205,918	40,343
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	51,994	1,076
Debt Securities, Available-for-sale, Unrealized Loss Position	807,916	277,697
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss	150,996	4,938
U.S. Government 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	83,992	100,813
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	1,478	1,988
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	138,881	48,714
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	13,420	1,286
Debt Securities, Available-for-sale, Unrealized Loss Position	222,873	149,527
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss	14,898	3,274
US Treasury Securities [Member]
Debt Securities, Available-for-sale [Line Items]
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	111,904	157,536
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	10,996	831
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	54,402	0
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	5,563	0
Debt Securities, Available-for-sale, Unrealized Loss Position	166,306	157,536
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss	16,559	831
Non-agency collateralized mortgage obligations [Member]
Debt Securities, Available-for-sale [Line Items]
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	291,301	212,259
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	60,781	955
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	5,664	0
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	782	0
Debt Securities, Available-for-sale, Unrealized Loss Position	296,965	212,259
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss	$ 61,563	$ 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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