GOODWILL AND INTANGIBLE ASSETS - Components of Intangible Assets (Details) - USD ($) $ in Millions	9 Months Ended	12 Months Ended
Sep. 30, 2018	Dec. 31, 2017
Finite and Indefinite-lived Intangible Assets
Gross carrying amount of Intangible assets (excluding MSRs)	$ 12,020	$ 11,894
Accumulated amortization of Intangible assets (excluding MSRs)	7,422	7,306
Net carrying amount of Intangible assets (excluding MSRs)	4,598	4,588
Gross carrying amount, Mortgage servicing rights (MSRs)	618	558
Mortgage servicing rights (MSRs)	618	558
Gross carrying amount of Intangible assets	12,638	12,452
Accumulated amortization of Intangible assets	7,422	7,306
Total intangible assets	5,216	5,146
Indefinite-lived intangible assets
Finite and Indefinite-lived Intangible Assets
Gross carrying amount of Intangible assets (excluding MSRs)	227	244
Accumulated amortization of Intangible assets (excluding MSRs)	0	0
Net carrying amount of Intangible assets (excluding MSRs)	227	244
Purchased credit card relationships
Finite and Indefinite-lived Intangible Assets
Gross carrying amount of Intangible assets (excluding MSRs)	5,732	5,375
Accumulated amortization of Intangible assets (excluding MSRs)	3,890	3,836
Net carrying amount of Intangible assets (excluding MSRs)	1,842	1,539
Credit card contract related intangibles
Finite and Indefinite-lived Intangible Assets
Gross carrying amount of Intangible assets (excluding MSRs)	5,042	5,045
Accumulated amortization of Intangible assets (excluding MSRs)	2,708	2,456
Net carrying amount of Intangible assets (excluding MSRs)	2,334	2,589
Core deposit intangibles
Finite and Indefinite-lived Intangible Assets
Gross carrying amount of Intangible assets (excluding MSRs)	438	639
Accumulated amortization of Intangible assets (excluding MSRs)	433	628
Net carrying amount of Intangible assets (excluding MSRs)	5	11
Other customer relationships
Finite and Indefinite-lived Intangible Assets
Gross carrying amount of Intangible assets (excluding MSRs)	463	459
Accumulated amortization of Intangible assets (excluding MSRs)	289	272
Net carrying amount of Intangible assets (excluding MSRs)	174	187
Present value of future profits
Finite and Indefinite-lived Intangible Assets
Gross carrying amount of Intangible assets (excluding MSRs)	34	32
Accumulated amortization of Intangible assets (excluding MSRs)	30	28
Net carrying amount of Intangible assets (excluding MSRs)	4	4
Other
Finite and Indefinite-lived Intangible Assets
Gross carrying amount of Intangible assets (excluding MSRs)	84	100
Accumulated amortization of Intangible assets (excluding MSRs)	72	86
Net carrying amount of Intangible assets (excluding MSRs)	$ 12	$ 14
Customer Concentration Risk \| American Airlines, Sears, The Home Depot, Costco and AT&T \| Intangible Assets, Excluding Mortgage Servicing Rights \| Credit card contract related intangibles
Finite and Indefinite-lived Intangible Assets
Concentration risk, percentage	97.00%	97.00%

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.

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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.

+ Details

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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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+ 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.

+ References

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.

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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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