INVESTMENT SECURITIES - Schedule of Unrealized Losses on Available-for-Sale Investment Securities (Details) - USD ($) $ in Thousands	Sep. 30, 2026	Dec. 31, 2025
Unrealized loss position for less than 12 months
Fair Value	$ 8,907,325	$ 2,436,978
Unrealized Loss	(243,729)	(23,476)
Unrealized loss position for more than 12 months
Fair Value	5,149,140	5,226,775
Unrealized Loss	(430,551)	(281,040)
Government/GSE guaranteed MBS
Unrealized loss position for less than 12 months
Fair Value	3,004,538	799,619
Unrealized Loss	(71,459)	(4,695)
Unrealized loss position for more than 12 months
Fair Value	2,019,379	2,008,388
Unrealized Loss	(138,228)	(84,539)
U.S. Treasuries
Unrealized loss position for less than 12 months
Fair Value	1,500,655	29,902
Unrealized Loss	(19,486)	(13)
Unrealized loss position for more than 12 months
Fair Value	0	95,270
Unrealized Loss	0	(35)
ABS
Unrealized loss position for less than 12 months
Fair Value	61,026
Unrealized Loss	(4,290)
Unrealized loss position for more than 12 months
Fair Value	0
Unrealized Loss	0
AgVantage
Unrealized loss position for less than 12 months
Fair Value	4,341,106	1,607,457
Unrealized Loss	(148,494)	(18,768)
Unrealized loss position for more than 12 months
Fair Value	3,129,761	3,123,117
Unrealized Loss	$ (292,323)	$ (196,466)

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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 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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