Investment Securities - Unrealized Losses on Securities Available-for-Sale (Details) - USD ($) $ in Thousands	Sep. 30, 2022	Dec. 31, 2021
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	$ 3,182,898	$ 5,102,495
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	349,824	63,559
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	2,688,829	322,496
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	(528,832)	(8,536)
Debt Securities, Available-for-sale, Unrealized Loss Position, Total	5,871,727	5,424,991
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss, Total	878,656	72,095
Agency residential MBS
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	828,719	2,502,536
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	154,049	31,670
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	1,462,515	57,329
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	(315,387)	(979)
Debt Securities, Available-for-sale, Unrealized Loss Position, Total	2,291,234	2,559,865
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss, Total	469,436	32,649
Agency commercial MBS
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	679,617	440,938
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	58,395	5,066
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	114,979	106,745
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	(21,474)	(4,147)
Debt Securities, Available-for-sale, Unrealized Loss Position, Total	794,596	547,683
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss, Total	79,869	9,213
Agency residential CMOs
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	518,065	216,445
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	31,153	3,757
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	218,418	67,340
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	(36,926)	(2,113)
Debt Securities, Available-for-sale, Unrealized Loss Position, Total	736,483	283,785
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss, Total	68,079	5,870
Municipal securities
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	325,040	505,080
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	47,929	6,965
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	83,882	29,726
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	(17,038)	(1,008)
Debt Securities, Available-for-sale, Unrealized Loss Position, Total	408,922	534,806
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss, Total	64,967	7,973
U.S. Treasury securities
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	117,110	628,767
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	16,858	8,298
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	546,279	0
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	(90,835)	0
Debt Securities, Available-for-sale, Unrealized Loss Position, Total	663,389	628,767
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss, Total	107,693	8,298
Corporate debt securities
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	341,017	32,761
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	28,429	757
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	4,525	0
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	(475)	0
Debt Securities, Available-for-sale, Unrealized Loss Position, Total	345,542	32,761
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss, Total	28,904	757
Collateralized loan obligations
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	260,188	137,619
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	7,935	374
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	93,574	43,730
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	(3,647)	(70)
Debt Securities, Available-for-sale, Unrealized Loss Position, Total	353,762	181,349
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss, Total	11,582	444
Private label residential CMOs
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	50,799	201,988
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	2,535	3,291
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	147,156	0
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	(41,289)	0
Debt Securities, Available-for-sale, Unrealized Loss Position, Total	197,955	201,988
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss, Total	43,824	3,291
Asset-backed securities
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	32,022	38,742
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	498	137
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	0	15,762
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	0	(187)
Debt Securities, Available-for-sale, Unrealized Loss Position, Total	32,022	54,504
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss, Total	498	324
Private label commercial MBS
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	11,695	397,619
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	696	3,244
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	17,483	0
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	(1,760)	0
Debt Securities, Available-for-sale, Unrealized Loss Position, Total	29,178	397,619
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss, Total	2,456	3,244
SBA securities
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	18,626	0
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	1,347	0
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	18	1,864
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	(1)	(32)
Debt Securities, Available-for-sale, Unrealized Loss Position, Total	18,644	1,864
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss, Total	$ 1,348	$ 32