Investment Securities - Unrealized Losses on Securities Available-for-Sale (Details) - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	$ 0	$ 0
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	0	0
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	2,173,331	2,298,565
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	(371,994)	(352,454)
Debt Securities, Available-for-sale, Unrealized Loss Position, Total	2,173,331	2,298,565
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss, Total	371,994	352,454
Agency residential MBS
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	0	0
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	0	0
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	1,137,469	1,187,609
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	(226,776)	(201,192)
Debt Securities, Available-for-sale, Unrealized Loss Position, Total	1,137,469	1,187,609
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss, Total	226,776	201,192
Agency commercial MBS
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	0	0
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	0	0
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	243,387	253,306
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	(16,729)	(15,333)
Debt Securities, Available-for-sale, Unrealized Loss Position, Total	243,387	253,306
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss, Total	16,729	15,333
Agency residential CMOs
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	0	0
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	0	0
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	281,569	265,431
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	(36,036)	(36,650)
Debt Securities, Available-for-sale, Unrealized Loss Position, Total	281,569	265,431
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss, Total	36,036	36,650
Municipal securities
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	0	0
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	0	0
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	33,259	284,334
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	(1,386)	(1,109)
Debt Securities, Available-for-sale, Unrealized Loss Position, Total	33,259	284,334
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss, Total	1,386	1,109
Corporate Debt Securities
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	0	0
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	0	0
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	274,022	19,952
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	(51,642)	(60,254)
Debt Securities, Available-for-sale, Unrealized Loss Position, Total	274,022	19,952
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss, Total	51,642	60,254
Collateralized loan obligations
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	0	0
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	0	0
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	17,811	66,886
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	(89)	(752)
Debt Securities, Available-for-sale, Unrealized Loss Position, Total	17,811	66,886
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss, Total	89	752
Private label commercial MBS
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	0	0
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	0	0
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	19,491	28,083
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	(1,234)	(1,313)
Debt Securities, Available-for-sale, Unrealized Loss Position, Total	19,491	28,083
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss, Total	1,234	1,313
SBA securities
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	0	0
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	0	0
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	12,911	13,739
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	(1,006)	(903)
Debt Securities, Available-for-sale, Unrealized Loss Position, Total	12,911	13,739
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss, Total	1,006	903
Private Label Collateralized Mortgage Obligations
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	0	0
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	0	0
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	153,412	158,412
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	(37,096)	(34,659)
Debt Securities, Available-for-sale, Unrealized Loss Position, Total	153,412	158,412
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss, Total	$ 37,096	34,659
Asset-backed Securities
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months		0
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss		0
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer		20,813
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss		(289)
Debt Securities, Available-for-sale, Unrealized Loss Position, Total		20,813
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss, Total		$ 289

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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