GOODWILL AND INTANGIBLE ASSETS - Components of Intangible Assets (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Finite and Indefinite-lived Intangible Assets
Gross carrying amount of Intangible assets (excluding MSRs)	$ 10,078	$ 10,210
Accumulated amortization of Intangible assets (excluding MSRs)	6,315	6,119
Net carrying amount of intangible assets (excluding MSRs)	3,763	4,091
Gross carrying amount, Mortgage servicing rights (MSRs)	665	404
Mortgage servicing rights (MSRs)	665	404
Gross carrying amount of Intangible assets	10,743	10,614
Accumulated amortization of intangible assets	6,315	6,119
Total intangible assets	4,428	4,495
Intangible assets amortization expense	352	360	$ 419
Finite-Lived Intangible Assets, Net, Amortization Expense, Fiscal Year Maturity [Abstract]
Expected amortization next year	373
Expected amortization in two years	381
Expected amortization in three years	388
Expected amortization in four years	348
Expected amortization in five years	341
Indefinite-lived intangible assets
Finite and Indefinite-lived Intangible Assets
Gross carrying amount of Intangible assets (excluding MSRs)	192	183
Net carrying amount of intangible assets (excluding MSRs)	192	183
Purchased credit card relationships
Finite and Indefinite-lived Intangible Assets
Gross carrying amount of Intangible assets (excluding MSRs)	5,513	5,579
Accumulated amortization of Intangible assets (excluding MSRs)	4,426	4,348
Net carrying amount of intangible assets (excluding MSRs)	1,087	1,231
Credit card contract related intangibles
Finite and Indefinite-lived Intangible Assets
Gross carrying amount of Intangible assets (excluding MSRs)	3,903	3,912
Accumulated amortization of Intangible assets (excluding MSRs)	1,518	1,372
Net carrying amount of intangible assets (excluding MSRs)	2,385	2,540
Core deposit intangibles
Finite and Indefinite-lived Intangible Assets
Gross carrying amount of Intangible assets (excluding MSRs)	37	39
Accumulated amortization of Intangible assets (excluding MSRs)	37	39
Net carrying amount of intangible assets (excluding MSRs)	0	0
Other customer relationships
Finite and Indefinite-lived Intangible Assets
Gross carrying amount of Intangible assets (excluding MSRs)	373	429
Accumulated amortization of Intangible assets (excluding MSRs)	283	305
Net carrying amount of intangible assets (excluding MSRs)	90	124
Present value of future profits
Finite and Indefinite-lived Intangible Assets
Gross carrying amount of Intangible assets (excluding MSRs)	32	31
Accumulated amortization of Intangible assets (excluding MSRs)	31	29
Net carrying amount of intangible assets (excluding MSRs)	1	2
Other
Finite and Indefinite-lived Intangible Assets
Gross carrying amount of Intangible assets (excluding MSRs)	28	37
Accumulated amortization of Intangible assets (excluding MSRs)	20	26
Net carrying amount of intangible assets (excluding MSRs)	$ 8	$ 11
American Airlines, Sears, The Home Depot and Costco \| Intangible Assets, Excluding Mortgage Servicing Rights \| Customer Concentration Risk \| Credit card contract related intangibles
Finite and Indefinite-lived Intangible Assets
Intangible assets, percent	97.00%	97.00%

No definition available.

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Sum of the carrying amounts of all intangible assets, excluding goodwill and excluding mortgage servicing rights, as of the balance sheet date, net of accumulated amortization and impairment charges.

+ References

No definition available.

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- Definition

This element represents the accumulated amortization of all intangible assets, excluding goodwill and mortgage servicing rights (MSRs), as of the balance sheet date.

+ References

No definition available.

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This element represents the gross carrying amounts of all intangible assets, excluding goodwill and mortgage servicing rights (MSRs), as of the balance sheet date.

+ References

No definition available.

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This element represents the sum of the carrying amounts of all intangible assets excluding goodwill but including mortgage servicing rights, as of the balance sheet date that is net of accumulated amortization and impairment charges.

+ References

No definition available.

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This element represents the accumulated amortization of all intangible assets excluding goodwill but including mortgage servicing rights (MSRs), as of the balance sheet date.

+ References

No definition available.

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This element represents the gross carrying amount of intangible assets excluding goodwill but including mortgage servicing rights (MSRs), as of the balance sheet date.

+ References

No definition available.

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The amount of mortgage servicing rights (MSRs) as of the balance sheet date.

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No definition available.

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This element represents the gross carrying amount of mortgage servicing rights (MSRs) as of the balance sheet date.

+ References

No definition available.

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- Definition

The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

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- Definition

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

+ References

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- Definition

Amount of amortization for assets, excluding financial assets and goodwill, lacking physical substance with finite life expected to be recognized in next fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

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- Definition

Amount of amortization for assets, excluding financial assets and goodwill, lacking physical substance with finite life expected to be recognized in fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

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Amount of amortization for assets, excluding financial assets and goodwill, lacking physical substance with finite life expected to be recognized in fourth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of amortization for assets, excluding financial assets and goodwill, lacking physical substance with finite life expected to be recognized in third fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

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Amount of amortization for assets, excluding financial assets and goodwill, lacking physical substance with finite life expected to be recognized in second fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

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