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DERIVATIVE INSTRUMENTS AND HEDGING ACTIVITIES (Derivative Gain (Loss) Recognized/Reclassified) (Details) - USD ($) $ in Millions | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2025 | Sep. 30, 2024 | Sep. 30, 2025 | Sep. 30, 2024
Derivative Instruments, Gain (Loss) [Line Items] |  |  |  |
Amount of gain (loss) reclassified from AOCI into income | $ (11) | $ (23) | $ (45) | $ (71)
Loss to be reclassified within the next 12 months into interest income |  |  | 37 |
Deferred losses | 48 |  | 48 |
Derivatives designated as accounting hedges: |  |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |  |
Effective portion of derivative gain (loss) deferred in AOCI | 0 | 3 | 8 | 1
Amount of gain (loss) reclassified from AOCI into income | (15) | (28) | (52) | (93)
Interest on fair value hedges | 12 | 22 | 34 | 65
Derivatives designated as accounting hedges: | Cash Flow Hedging |  |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |  |
Terminated or redesignated, unamortized basis adjustments, debt | 34 | 41 | 34 | 41
Terminated or redesignated, unamortized basis adjustments, assets | 3 | 3 | 3 | 3
Derivatives designated as accounting hedges: | Cash Flow Hedging | Hedges of floating-rate assets |  |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |  |
Effective portion of derivative gain (loss) deferred in AOCI | 0 | 5 | 8 | (2)
Amount of gain (loss) reclassified from AOCI into income | (15) | (30) | (53) | (99)
Interest on fair value hedges | 0 | 0 | 0 | 0
Derivatives designated as accounting hedges: | Cash Flow Hedging | Hedges of floating-rate liabilities |  |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |  |
Effective portion of derivative gain (loss) deferred in AOCI | 0 | (2) | 0 | 3
Amount of gain (loss) reclassified from AOCI into income | 0 | 2 | 1 | 6
Interest on fair value hedges | 0 | 0 | 0 | 0
Derivatives designated as accounting hedges: | Fair Value Hedging | Hedges of fixed-rate assets |  |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |  |
Effective portion of derivative gain (loss) deferred in AOCI | 0 | 0 | 0 | 0
Amount of gain (loss) reclassified from AOCI into income | 0 | 0 | 0 | 0
Interest on fair value hedges | 15 | 24 | (8) | (5)
Derivatives designated as accounting hedges: | Fair Value Hedging | Hedges of fixed-rate liabilities |  |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |  |
Effective portion of derivative gain (loss) deferred in AOCI | 0 | 0 | 0 | 0
Amount of gain (loss) reclassified from AOCI into income | 0 | 0 | 0 | 0
Interest on fair value hedges | $ (3) | $ (2) | $ 42 | $ 70

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- Definition Amount, after tax, of accumulated gain (loss) on derivative instrument designated and qualifying as cash flow hedge included in assessment of hedge effectiveness. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 220 -SubTopic 10 -Name Accounting Standards Codification -Section 45 -Paragraph 11 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482790/220-10-45-11 + Details
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