FINANCIAL DERIVATIVES - Schedule of Hedged Items in Fair Value Hedging Relationships (Details) - USD ($) $ in Thousands	Sep. 30, 2026	Dec. 31, 2025
HedgedItemsinFairValueHedgingRelationship [Line Items]
Available-for-sale securities, amortized cost	$ 9,000,000	$ 8,000,000
Closed portfolio of securities hedged, amortized cost	800,000
Designated as hedge
HedgedItemsinFairValueHedgingRelationship [Line Items]
Closed portfolio of securities hedged, amortized cost	244,200
Notes Payable
HedgedItemsinFairValueHedgingRelationship [Line Items]
Carrying amount of hedged liabilities	(15,129,333)	(11,837,713)
Cumulative amount of fair value hedging adjustments, hedged liabilities	260,078	(6,690)
Available-for-sale securities
HedgedItemsinFairValueHedgingRelationship [Line Items]
Carrying amount of hedged assets	8,387,284	7,818,278
Cumulative amount of fair value hedging adjustments, hedged assets	(565,219)	(235,989)
Loans held for investment, at amortized cost
HedgedItemsinFairValueHedgingRelationship [Line Items]
Carrying amount of hedged assets	3,399,845	2,278,212
Cumulative amount of fair value hedging adjustments, hedged assets	$ (518,220)	$ (331,315)

[Line Items] for HedgedItemsinFairValueHedgingRelationship [Table]

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Amortized cost excluding accrued interest, after allowance for credit loss, of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

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- Definition

Amount of asset hedged in fair value hedging relationship.

+ References

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- Definition

Amount of cumulative increase (decrease) in fair value of hedged asset in fair value hedge, attributable to hedged risk. Excludes cumulative basis adjustment related to foreign exchange risk.

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Amount of liability hedged in fair value hedging relationship.

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Amount of cumulative increase (decrease) in fair value of hedged liability in fair value hedge, attributable to hedged risk. Excludes cumulative basis adjustment related to foreign exchange risk.

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- Definition

Amortized cost of closed portfolio of financial asset used to designate hedging relationship in which hedged item is expected to be outstanding for designated hedged period.

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