DERIVATIVES - Amounts Recorded in Balance Sheet (Details) - USD ($) $ in Millions	Sep. 30, 2022	Dec. 31, 2021
Derivative [Line Items]
Last-of-layer hedging amount		$ 2,000
Carrying value of hedged asset in lay-of-layer hedging relationship		6,000
Long-term borrowed funds
Derivative [Line Items]
Carrying amount of hedged liabilities	$ 970	2,239
Cumulative amount of fair value hedging adjustments included in the carrying amount of long-term borrowed funds	(29)	42
Debt securities available for sale
Derivative [Line Items]
Carrying amount of hedged assets	0	6,042
Cumulative amount of fair value hedging adjustments included in the carrying amount of the hedged items	0	$ 29
Loans and leases held for sale
Derivative [Line Items]
Carrying amount of hedged assets	484
Cumulative amount of fair value hedging adjustments included in the carrying amount of the hedged items	$ (15)

Amortized cost of closed portfolio of prepayable financial asset and beneficial interest secured by prepayable financial instrument, used to designate hedging relationship in which hedged item is last layer expected to be remaining at end of hedging relationship.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4EEE
-Subparagraph (a)
-URI https://asc.fasb.org/extlink&oid=125515794&loc=SL109999718-113959

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Amount of asset hedged in fair value hedging relationship.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4EE
-Subparagraph (a)
-URI https://asc.fasb.org/extlink&oid=125515794&loc=SL109999712-113959

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Amount of cumulative increase (decrease) in fair value of hedged asset in fair value hedge, attributable to hedged risk.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4EE
-Subparagraph (b)
-URI https://asc.fasb.org/extlink&oid=125515794&loc=SL109999712-113959

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Amount of asset hedged in last of layer, expected to be remaining at end of hedging relationship.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4EEE
-Subparagraph (b)
-URI https://asc.fasb.org/extlink&oid=125515794&loc=SL109999718-113959

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Amount of liability hedged in fair value hedging relationship.

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Amount of cumulative increase (decrease) in fair value of hedged liability in fair value hedge, attributable to hedged risk.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4EE
-Subparagraph (b)
-URI https://asc.fasb.org/extlink&oid=125515794&loc=SL109999712-113959

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