Investment Securities - Unrealized Losses on Securities Available-for-Sale (Details) - USD ($) $ in Thousands	Jun. 30, 2022	Dec. 31, 2021
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	$ 5,870,242	$ 5,102,495
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	541,052	63,559
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	486,109	322,496
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	54,458	8,536
Debt Securities, Available-for-sale, Unrealized Loss Position, Total	6,356,351	5,424,991
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss, Total	595,510	72,095
Agency residential MBS
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	2,232,774	2,502,536
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	288,563	31,670
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	262,847	57,329
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	33,107	979
Debt Securities, Available-for-sale, Unrealized Loss Position, Total	2,495,621	2,559,865
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss, Total	321,670	32,649
Agency commercial MBS
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	851,935	440,938
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	39,376	5,066
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	41,199	106,745
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	5,335	4,147
Debt Securities, Available-for-sale, Unrealized Loss Position, Total	893,134	547,683
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss, Total	44,711	9,213
Agency residential CMOs
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	707,516	216,445
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	29,892	3,757
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	88,546	67,340
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	11,416	2,113
Debt Securities, Available-for-sale, Unrealized Loss Position, Total	796,062	283,785
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss, Total	41,308	5,870
Municipal securities
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	463,945	505,080
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	45,459	6,965
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	0	29,726
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	0	1,008
Debt Securities, Available-for-sale, Unrealized Loss Position, Total	463,945	534,806
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss, Total	45,459	7,973
U.S. Treasury securities
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	696,054	628,767
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	74,965	8,298
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	0	0
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	0	0
Debt Securities, Available-for-sale, Unrealized Loss Position, Total	696,054	628,767
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss, Total	74,965	8,298
Corporate debt securities
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	355,637	32,761
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	19,080	757
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	0	0
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	0	0
Debt Securities, Available-for-sale, Unrealized Loss Position, Total	355,637	32,761
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss, Total	19,080	757
Collateralized loan obligations
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	269,865	137,619
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	9,256	374
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	82,425	43,730
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	3,808	70
Debt Securities, Available-for-sale, Unrealized Loss Position, Total	352,290	181,349
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss, Total	13,064	444
Private label residential CMOs
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	216,103	201,988
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	32,052	3,291
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	0	0
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	0	0
Debt Securities, Available-for-sale, Unrealized Loss Position, Total	216,103	201,988
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss, Total	32,052	3,291
Asset-backed securities
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	31,261	38,742
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	711	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	31,261	54,504
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss, Total	711	324
Private label commercial MBS
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	23,206	397,619
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	1,177	3,244
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	9,311	0
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	718	0
Debt Securities, Available-for-sale, Unrealized Loss Position, Total	32,517	397,619
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss, Total	1,895	3,244
SBA securities
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	21,946	0
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	521	0
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	1,781	1,864
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	74	32
Debt Securities, Available-for-sale, Unrealized Loss Position, Total	23,727	1,864
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss, Total	$ 595	$ 32

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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Amount of accumulated unrealized loss on 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 12 months or longer, without allowance for credit loss. Includes beneficial interest in securitized financial asset.

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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 less than 12 months, without allowance for credit loss. Includes beneficial interest in securitized financial asset.

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Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in unrealized loss position without allowance for credit loss.

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