Investment Securities - Schedule of Investment Securities in Gross Unrealized Loss Position (Details) - USD ($) $ in Thousands	Mar. 31, 2026	Dec. 31, 2025
Debt Securities, Available-for-sale [Line Items]
Investments in AFS debt securities, less than 12 months, fair value	$ 1,694,140	$ 276,280
Investments in AFS debt securities, less than 12 months, gross unrealized losses	(11,014)	(1,061)
Investments in AFS debt securities, 12 months or longer, fair value	12,980	20,680
Investments in AFS debt securities, 12 months or longer, gross unrealized losses	(957)	(983)
Investments in AFS debt securities, total, fair value	1,707,120	296,960
Investments in AFS debt securities, total, gross unrealized losses	(11,971)	(2,044)
U.S. Treasury securities
Debt Securities, Available-for-sale [Line Items]
Investments in AFS debt securities, less than 12 months, fair value	172,113	49,962
Investments in AFS debt securities, less than 12 months, gross unrealized losses	(1,500)	(465)
Investments in AFS debt securities, 12 months or longer, fair value	0	0
Investments in AFS debt securities, 12 months or longer, gross unrealized losses	0	0
Investments in AFS debt securities, total, fair value	172,113	49,962
Investments in AFS debt securities, total, gross unrealized losses	(1,500)	(465)
Agency mortgage-backed securities
Debt Securities, Available-for-sale [Line Items]
Investments in AFS debt securities, less than 12 months, fair value	1,502,676	202,845
Investments in AFS debt securities, less than 12 months, gross unrealized losses	(9,309)	(497)
Investments in AFS debt securities, 12 months or longer, fair value	11,971	19,661
Investments in AFS debt securities, 12 months or longer, gross unrealized losses	(823)	(855)
Investments in AFS debt securities, total, fair value	1,514,647	222,506
Investments in AFS debt securities, total, gross unrealized losses	(10,132)	(1,352)
Corporate bonds
Debt Securities, Available-for-sale [Line Items]
Investments in AFS debt securities, less than 12 months, fair value	0	0
Investments in AFS debt securities, less than 12 months, gross unrealized losses	0	0
Investments in AFS debt securities, 12 months or longer, fair value	184	185
Investments in AFS debt securities, 12 months or longer, gross unrealized losses	(3)	(2)
Investments in AFS debt securities, total, fair value	184	185
Investments in AFS debt securities, total, gross unrealized losses	(3)	(2)
Asset-backed bonds
Debt Securities, Available-for-sale [Line Items]
Investments in AFS debt securities, less than 12 months, fair value	15,925	19,703
Investments in AFS debt securities, less than 12 months, gross unrealized losses	(62)	(6)
Investments in AFS debt securities, 12 months or longer, fair value	0	0
Investments in AFS debt securities, 12 months or longer, gross unrealized losses	0	0
Investments in AFS debt securities, total, fair value	15,925	19,703
Investments in AFS debt securities, total, gross unrealized losses	(62)	(6)
Residual investments
Debt Securities, Available-for-sale [Line Items]
Investments in AFS debt securities, less than 12 months, fair value	3,426	3,770
Investments in AFS debt securities, less than 12 months, gross unrealized losses	(143)	(93)
Investments in AFS debt securities, 12 months or longer, fair value	0	0
Investments in AFS debt securities, 12 months or longer, gross unrealized losses	0	0
Investments in AFS debt securities, total, fair value	3,426	3,770
Investments in AFS debt securities, total, gross unrealized losses	(143)	(93)
Other
Debt Securities, Available-for-sale [Line Items]
Investments in AFS debt securities, less than 12 months, fair value	0	0
Investments in AFS debt securities, less than 12 months, gross unrealized losses	0	0
Investments in AFS debt securities, 12 months or longer, fair value	825	834
Investments in AFS debt securities, 12 months or longer, gross unrealized losses	(131)	(126)
Investments in AFS debt securities, total, fair value	825	834
Investments in AFS debt securities, total, gross unrealized losses	$ (131)	$ (126)

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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