GOODWILL AND INTANGIBLE ASSETS - Components of Intangible Assets (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Finite and Indefinite-lived Intangible Assets
Gross carrying amount of Intangible assets (excluding MSRs)	$ 10,454	$ 10,119
Accumulated amortization of Intangible assets (excluding MSRs)	6,720	6,389
Net carrying amount of intangible assets (excluding MSRs)	3,734	3,730
Gross carrying amount, Mortgage servicing rights (MSRs)	760	691
Mortgage servicing rights (MSRs)	760	691
Gross carrying amount of Intangible assets	11,214	10,810
Accumulated amortization of intangible assets	6,720	6,389
Total intangible assets	4,494	4,421
Intangible assets amortization expense	371	370	$ 352
Finite-Lived Intangible Assets, Net, Amortization Expense, Fiscal Year Maturity [Abstract]
Expected amortization next year	243
Expected amortization in two years	233
Expected amortization in three years	225
Expected amortization in four years	213
Expected amortization in five years	182
Indefinite-lived intangible assets
Finite and Indefinite-lived Intangible Assets
Gross carrying amount of Intangible assets (excluding MSRs)	197	240
Net carrying amount of intangible assets (excluding MSRs)	197	240
Purchased credit card relationships
Finite and Indefinite-lived Intangible Assets
Gross carrying amount of Intangible assets (excluding MSRs)	5,315	5,302
Accumulated amortization of Intangible assets (excluding MSRs)	4,507	4,365
Net carrying amount of intangible assets (excluding MSRs)	$ 808	937
Useful life	10 years
Credit card contract related intangibles
Finite and Indefinite-lived Intangible Assets
Gross carrying amount of Intangible assets (excluding MSRs)	$ 4,586	4,177
Accumulated amortization of Intangible assets (excluding MSRs)	1,905	1,698
Net carrying amount of intangible assets (excluding MSRs)	$ 2,681	2,479
Useful life	20 years
Other customer relationships
Finite and Indefinite-lived Intangible Assets
Gross carrying amount of Intangible assets (excluding MSRs)	$ 325	363
Accumulated amortization of Intangible assets (excluding MSRs)	278	290
Net carrying amount of intangible assets (excluding MSRs)	47	73
Present value of future profits
Finite and Indefinite-lived Intangible Assets
Gross carrying amount of Intangible assets (excluding MSRs)	31	37
Accumulated amortization of Intangible assets (excluding MSRs)	30	36
Net carrying amount of intangible assets (excluding MSRs)	$ 1	$ 1

No definition available.

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- Definition

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.

+ Details

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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.

+ Details

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- Definition

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.

+ Details

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- Definition

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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- Definition

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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- Definition

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.

+ Details

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- Definition

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

+ References

No definition available.

+ Details

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- Definition

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

+ References

No definition available.

+ Details

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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.

+ References

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- Definition

Useful life of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

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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

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 350
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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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- Definition

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).

+ 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 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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- Definition

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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- References

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