GOODWILL AND INTANGIBLE ASSETS - Changes in Intangible Assets (Details) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
Mar. 31, 2022	Dec. 31, 2021
Finite and Indefinite-lived Intangible Assets
Beginning balance	$ 4,091
Acquisitions/renewals/ divestitures	5
Amortization	(94)
Impairments	0
FX translation and other	0
Ending balance	4,002	$ 4,091
Mortgage servicing rights (MSRs)	520	404
Total intangible assets	4,522	4,495
Indefinite-lived intangible assets
Finite and Indefinite-lived Intangible Assets
Beginning balance	183
Acquisitions/renewals/ divestitures	0
Amortization	0
Impairments	0
FX translation and other	5
Ending balance	188	183
Purchased credit card relationships
Finite and Indefinite-lived Intangible Assets
Beginning balance	1,231
Acquisitions/renewals/ divestitures	0
Amortization	(36)
Impairments	0
FX translation and other	0
Ending balance	1,195	1,231
Credit card contract related intangibles
Finite and Indefinite-lived Intangible Assets
Beginning balance	2,540
Acquisitions/renewals/ divestitures	0
Amortization	(38)
Impairments	0
FX translation and other	0
Ending balance	2,502	2,540
Core deposit intangibles
Finite and Indefinite-lived Intangible Assets
Beginning balance	0
Acquisitions/renewals/ divestitures	0
Amortization	0
Impairments	0
FX translation and other	0
Ending balance	0	0
Other customer relationships
Finite and Indefinite-lived Intangible Assets
Beginning balance	124
Acquisitions/renewals/ divestitures	2
Amortization	(7)
Impairments	0
FX translation and other	(4)
Ending balance	115	124
Present value of future profits
Finite and Indefinite-lived Intangible Assets
Beginning balance	2
Acquisitions/renewals/ divestitures	0
Amortization	0
Impairments	0
FX translation and other	0
Ending balance	2	2
Other
Finite and Indefinite-lived Intangible Assets
Beginning balance	11
Acquisitions/renewals/ divestitures	3
Amortization	(13)
Impairments	0
FX translation and other	(1)
Ending balance	$ 0	$ 11
American Airlines, Costco, The Home Depot and AT&T \| Customer Concentration Risk \| Intangible Assets, Excluding Mortgage Servicing Rights \| Credit card contract related intangibles
Finite and Indefinite-lived Intangible Assets
Concentration risk, percentage	97.00%	97.00%

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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.

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Intangible Assets, Excluding Mortgage Servicing Rights Acquisitions (Divestitures)

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This element represents the aggregate amount of amortization of intangible assets excluding mortgage servicing rights (MSRs) during the period.

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This element represents the aggregate amount of impairment of intangible assets excluding mortgage servicing rights (MSRs) during the period.

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No definition available.

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This element represents net changes to the recorded value of intangible assets excluding mortgage servicing rights (MSRs), due to foreign currency translation adjustments and purchase accounting adjustments.

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

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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

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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