Customer Deposits - Categorized as Interest or Non-interest Bearing (Details) - USD ($) $ in Millions	Sep. 30, 2025	Dec. 31, 2024
U.S.:
Interest-bearing	$ 148,924	$ 138,433
Non-interest-bearing (includes Card Member credit balances of: 2025, $454; 2024, $513)	521	566
Non-U.S.:
Interest-bearing	18	17
Non-interest-bearing (includes Card Member credit balances of: 2025, $417; 2024, $395)	420	397
Total customer deposits	149,883	139,413
Card Member Credit Balances
U.S.:
Non-interest-bearing (includes Card Member credit balances of: 2025, $454; 2024, $513)	454	513
Non-U.S.:
Non-interest-bearing (includes Card Member credit balances of: 2025, $417; 2024, $395)	$ 417	$ 395

The aggregate of all deposit liabilities held by the entity, including foreign and domestic, interest and noninterest bearing; may include demand deposits, saving deposits, Negotiable Order of Withdrawal (NOW) and time deposits among others.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 942
-SubTopic 210
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(12))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478546/942-210-S99-1

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- References

No definition available.

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- References

No definition available.

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- Definition

Total amount of interest-bearing domestic deposit liabilities, which may include brokered, retail, demand, checking, notice of withdrawal, money market and other interest-bearing deposits.

+ References

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- Definition

Amount of foreign interest-bearing deposits held by the entity.

+ References

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- Definition

Amount of domestic noninterest-bearing deposits held by the entity, which may include demand deposits, checking, brokered and retail deposits.

+ References

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- Definition

Amount of foreign noninterest-bearing deposits held by the entity which may include demand deposits, checking, brokered and retail deposits.

+ References

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