Investment Securities - Unrealized Losses on Securities Available-for-Sale (Details) - USD ($) $ in Thousands	Jun. 30, 2023	Dec. 31, 2022
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	$ 22,218	$ 1,057,030
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	1,521	101,408
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	4,681,342	3,777,773
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	(805,785)	(709,728)
Debt Securities, Available-for-sale, Unrealized Loss Position, Total	4,703,560	4,834,803
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss, Total	807,306	811,136
Agency residential MBS
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	6,358	52,556
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	400	6,193
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	2,162,255	2,189,485
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	(423,331)	(436,803)
Debt Securities, Available-for-sale, Unrealized Loss Position, Total	2,168,613	2,242,041
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss, Total	423,731	442,996
Agency commercial MBS
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	0	316,892
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	0	31,139
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	479,957	170,714
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	(60,492)	(30,747)
Debt Securities, Available-for-sale, Unrealized Loss Position, Total	479,957	487,606
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss, Total	60,492	61,886
Agency residential CMOs
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	701	245,755
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	31	22,748
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	438,527	211,309
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	(60,843)	(37,363)
Debt Securities, Available-for-sale, Unrealized Loss Position, Total	439,228	457,064
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss, Total	60,874	60,111
Municipal securities
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	1,162	37,380
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	87	3,129
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	341,627	298,266
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	(52,324)	(57,269)
Debt Securities, Available-for-sale, Unrealized Loss Position, Total	342,789	335,646
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss, Total	52,411	60,398
U.S. Treasury securities
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	0	4,972
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	0	26
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	668,123	665,098
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	(98,145)	(101,049)
Debt Securities, Available-for-sale, Unrealized Loss Position, Total	668,123	670,070
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss, Total	98,145	101,075
Corporate Debt Securities
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	13,997	302,643
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	1,003	32,124
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	266,516	4,256
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	(63,214)	(744)
Debt Securities, Available-for-sale, Unrealized Loss Position, Total	280,513	306,899
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss, Total	64,217	32,868
Collateralized loan obligations
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	0	27,704
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	0	1,818
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	104,823	74,558
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	(4,345)	(5,080)
Debt Securities, Available-for-sale, Unrealized Loss Position, Total	104,823	102,262
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss, Total	4,345	6,898
Private label commercial MBS
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	0	10,204
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	0	508
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	23,200	16,623
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	(1,937)	(1,568)
Debt Securities, Available-for-sale, Unrealized Loss Position, Total	23,200	26,827
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss, Total	1,937	2,076
SBA securities
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	0	17,250
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	0	1,274
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	15,082	0
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	(1,278)	0
Debt Securities, Available-for-sale, Unrealized Loss Position, Total	15,082	17,250
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss, Total	1,278	1,274
Private Label Collateralized Mortgage Obligations
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	0	19,261
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	0	1,294
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	159,507	147,464
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	(39,485)	(39,105)
Debt Securities, Available-for-sale, Unrealized Loss Position, Total	159,507	166,725
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss, Total	39,485	40,399
Asset-backed Securities
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	0	22,413
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	0	1,155
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	21,725	0
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	(391)	0
Debt Securities, Available-for-sale, Unrealized Loss Position, Total	21,725	22,413
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss, Total	$ 391	$ 1,155