Investment Securities - Unrealized Losses on Securities Available-for-Sale (Details) - USD ($) $ in Thousands	Mar. 31, 2023	Dec. 31, 2022
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	$ 208,086	$ 1,057,030
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	23,552	101,408
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	4,640,520	3,777,773
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	(719,607)	(709,728)
Debt Securities, Available-for-sale, Unrealized Loss Position, Total	4,848,606	4,834,803
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss, Total	743,159	811,136
Agency residential MBS
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	6,665	52,556
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	306	6,193
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	2,242,415	2,189,485
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	(396,589)	(436,803)
Debt Securities, Available-for-sale, Unrealized Loss Position, Total	2,249,080	2,242,041
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss, Total	396,895	442,996
Agency commercial MBS
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	20,806	316,892
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	977	31,139
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	470,875	170,714
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	(52,822)	(30,747)
Debt Securities, Available-for-sale, Unrealized Loss Position, Total	491,681	487,606
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss, Total	53,799	61,886
Agency residential CMOs
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	35,116	245,755
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	2,707	22,748
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	420,566	211,309
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	(50,914)	(37,363)
Debt Securities, Available-for-sale, Unrealized Loss Position, Total	455,682	457,064
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss, Total	53,621	60,111
Municipal securities
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	836	37,380
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	44	3,129
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	344,803	298,266
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	(50,026)	(57,269)
Debt Securities, Available-for-sale, Unrealized Loss Position, Total	345,639	335,646
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss, Total	50,070	60,398
U.S. Treasury securities
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	4,993	4,972
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	7	26
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	680,443	665,098
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	(85,765)	(101,049)
Debt Securities, Available-for-sale, Unrealized Loss Position, Total	685,436	670,070
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss, Total	85,772	101,075
Corporate Debt Securities
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	119,754	302,643
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	18,667	32,124
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	170,040	4,256
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	(36,286)	(744)
Debt Securities, Available-for-sale, Unrealized Loss Position, Total	289,794	306,899
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss, Total	54,953	32,868
Collateralized loan obligations
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	18,690	27,704
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	838	1,818
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	84,304	74,558
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	(5,334)	(5,080)
Debt Securities, Available-for-sale, Unrealized Loss Position, Total	102,994	102,262
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss, Total	6,172	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	25,534	16,623
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	(1,796)	(1,568)
Debt Securities, Available-for-sale, Unrealized Loss Position, Total	25,534	26,827
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss, Total	1,796	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	15,906	0
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	(989)	0
Debt Securities, Available-for-sale, Unrealized Loss Position, Total	15,906	17,250
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss, Total	989	1,274
Private Label Collateralized Mortgage Obligations
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	1,226	19,261
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	6	1,294
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	163,177	147,464
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	(38,679)	(39,105)
Debt Securities, Available-for-sale, Unrealized Loss Position, Total	164,403	166,725
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss, Total	38,685	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	22,457	0
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	(407)	0
Debt Securities, Available-for-sale, Unrealized Loss Position, Total	22,457	22,413
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss, Total	$ 407	$ 1,155

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 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 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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