Investment Securities - Gross Gains and Losses (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Debt Securities, Available-for-sale [Line Items]
Amortized cost	$ 2,791,843	$ 2,156,095
Gross unrealized gains	8	1,193
Gross unrealized losses	(428,164)	(41,787)
Fair value	2,363,687	2,115,501
Corporate bonds
Debt Securities, Available-for-sale [Line Items]
Amortized cost	10,000	10,000
Gross unrealized gains	0	0
Gross unrealized losses	(654)	(27)
Fair value	9,346	9,973
Agency bond securities
Debt Securities, Available-for-sale [Line Items]
Amortized cost	240,272	230,841
Gross unrealized gains	0	0
Gross unrealized losses	(47,166)	(9,245)
Fair value	193,106	221,596
Agency mortgage-backed securities
Debt Securities, Available-for-sale [Line Items]
Amortized cost	2,511,958	1,879,793
Gross unrealized gains	8	806
Gross unrealized losses	(373,704)	(32,268)
Fair value	2,138,262	1,848,331
Municipal bonds
Debt Securities, Available-for-sale [Line Items]
Amortized cost	29,613	28,135
Gross unrealized gains	0	288
Gross unrealized losses	(6,640)	(243)
Fair value	$ 22,973	28,180
Asset-backed securities
Debt Securities, Available-for-sale [Line Items]
Amortized cost		7,326
Gross unrealized gains		99
Gross unrealized losses		(4)
Fair value		$ 7,421

Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amount, before tax, of unrealized loss in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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