FAIR VALUE - Schedule of Difference Between Fair Value and Principal Balance of LHFS (Details) - USD ($) $ in Millions	Sep. 30, 2026	Dec. 31, 2025
Difference
Loan, held-for-sale, fair value	$ 1,700	$ 1,500
Nonrecurring
Difference
Loan, held-for-sale, fair value	288	55
LHFS
Fair Value
LHFS	1,685	1,531
Principal Balance
LHFS	1,668	1,484
Difference
LHFS	17	47
RICs HFI
Fair Value
RICs HFI	3	5
Principal Balance
RICs HFI	3	5
Difference
RICs HFI	$ 0	$ 0

Fair Value, Option, Loans Held as Assets, Aggregate Amount

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- Definition

Fair Value, Option, Loans Held as Assets, Aggregate Unpaid Principal Balance

+ References

No definition available.

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- Definition

Fair Value, Option, Loans Held for Sale, Aggregate Amount

+ References

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Fair Value Option, Aggregate Unpaid Principal Balance [Abstract]

+ References

No definition available.

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- Definition

Unpaid principal balance of loans held-for-sale.

+ References

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- Definition

This item represents the difference between the aggregate fair value and the aggregate unpaid principal balance of loans and long-term receivables (other than securities categorized as trading, available-for-sale or held-to-maturity) that have contractual principal amounts and for which the fair value option has been elected.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 825
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 28
-Subparagraph (d)(1)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482907/825-10-50-28

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For loans held as assets for which the fair value option has been elected, this item represents the difference between the aggregate fair value and the aggregate unpaid principal balance of those loans that are 90 days or more past due, in nonaccrual status, or both.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 825
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 28
-Subparagraph (e)(3)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482907/825-10-50-28

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- Definition

Fair value portion of loans held-for-sale including, but not limited to, mortgage loans and finance receivables.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (bbb)(2)(i)
-Publisher FASB
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