Loans and Card Member Receivables (Details 4) account in Thousands, $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2021 USD ($) account	Sep. 30, 2020 USD ($) account	Sep. 30, 2021 USD ($) account	Sep. 30, 2020 USD ($) account
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Accounts \| account	32	92	106	262
Account Balances \| $	$ 293	$ 1,045	$ 962	$ 3,315
Card Member Loans
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Accounts \| account	26	76	87	216
Account Balances \| $	$ 177	$ 649	$ 636	$ 1,947
Average Interest Rate Reduction (as a percentage)	13.00%	14.00%	13.00%	14.00%
Card Member Receivables
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Accounts \| account	5	13	16	38
Account Balances \| $	$ 114	$ 231	$ 314	$ 1,049
Average Payment Term Extension (in months)	17 months	18 months	18 months	19 months
Other Loans
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Accounts \| account	1	3	3	8
Account Balances \| $	$ 2	$ 165	$ 12	$ 319
Average Interest Rate Reduction (as a percentage)	3.00%	3.00%	3.00%	3.00%
Average Payment Term Extension (in months)	17 months	17 months	16 months	16 months

The average basis point reduction in interest rate by class of Financial Instrument

No definition available.

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- Definition

The average period for payment term extension for cardmember receivables modified in a TDR.

+ References

No definition available.

+ Details

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Data Type:	xbrli:durationItemType
Balance Type:	na
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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Number of financing receivables that have been modified by troubled debt restructurings.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 33
-URI http://asc.fasb.org/extlink&oid=123577603&loc=SL6953676-111524

+ Details

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- Definition

Amount, before troubled debt restructuring, of financing receivable to be modified.

+ References

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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- Details

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- Details

Name:	us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=axp_CardmemberReceivablesMember
Namespace Prefix:
Data Type:	na
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- Details

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Data Type:	na
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