DERIVATIVES - Narrative (Details) - USD ($) $ in Millions	Dec. 31, 2025	Dec. 31, 2024
Derivative [Line Items]
Notional amount	$ 303,721	$ 279,484
Net loss (pre-tax) on derivatives expected to be reclassified in next 12 months	230
Prepayable Fixed-Rate Afs Securities Portfolio
Derivative [Line Items]
Carrying amount of hedge	3,800	4,700
Nonprepayable Fixed-Rate Afs Securities Portfolio
Derivative [Line Items]
Carrying amount of hedge	2,800	$ 3,100
Interest rate contracts \| Cash Flow Hedging
Derivative [Line Items]
Notional amount	$ 1,500

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
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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-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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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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