DERIVATIVES - Narrative (Details) - USD ($) $ in Millions	Mar. 31, 2026	Dec. 31, 2025
Derivative [Line Items]
Notional amount	$ 308,175	$ 303,721
Net loss (pre-tax) on derivatives expected to be reclassified in next 12 months	188
Prepayable Fixed-Rate Afs Securities Portfolio
Derivative [Line Items]
Carrying amount of hedged assets	3,800	3,800
Nonprepayable Fixed-Rate Afs Securities Portfolio
Derivative [Line Items]
Carrying amount of hedged assets	$ 2,000	$ 2,800

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 815
-SubTopic 20
-Name Accounting Standards Codification
-Section 25
-Paragraph 6A
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480682/815-20-25-6A

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 815
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Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
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Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef
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+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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