FINANCIAL DERIVATIVES - Schedule of Hedged Items in Fair Value Hedging Relationships (Details) - USD ($) $ in Thousands	Mar. 31, 2026	Dec. 31, 2025
Investment securities, Available-for-Sale, at fair value
HedgedItemsinFairValueHedgingRelationship [Line Items]
Carrying Amount of Hedged Assets/(Liabilities)	$ 7,999,738	$ 7,818,278
Cumulative amount of fair value hedging adjustments included in the carrying amount of hedged assets	(265,878)	(235,989)
Amortized cost	8,300,000	8,000,000
Loans held for investment, at amortized cost
HedgedItemsinFairValueHedgingRelationship [Line Items]
Carrying Amount of Hedged Assets/(Liabilities)	2,427,133	2,278,212
Cumulative amount of fair value hedging adjustments included in the carrying amount of hedged assets	(333,449)	(331,315)
Notes Payable
HedgedItemsinFairValueHedgingRelationship [Line Items]
Carrying Amount of Hedged Assets/(Liabilities)	(12,641,440)	(11,837,713)
Cumulative amount of fair value hedging adjustments included in the carrying amount of hedged liabilities	$ 41,224	$ (6,690)

[Line Items] for HedgedItemsinFairValueHedgingRelationship [Table]

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- Definition

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

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 326
-SubTopic 30
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479130/326-30-45-1

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- Definition

Amount of hedged item in hedging relationship. Excludes hedged asset or liability.

+ References

No definition available.

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 815
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 4EE
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480434/815-10-50-4EE

Reference 2: http://www.xbrl.org/2003/role/exampleRef
-Topic 815
-SubTopic 10
-Name Accounting Standards Codification
-Section 55
-Paragraph 181
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480401/815-10-55-181

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- Definition

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.

+ References

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