Loans and Card Member Receivables (Details) - USD ($) $ in Millions	Sep. 30, 2020	Dec. 31, 2019
Accounts Receivable and Loans Textuals
Card Member loans	$ 69,606	$ 87,381
Loans segment information
Less: Reserve for credit losses	5,688	2,383
Card Member loans, net	63,918	84,998
Other loans, net	3,144	4,626
Other loans, reserves for credit losses	370	152
PPP Loans
Loans segment information
Gross PPP loans	700
Variable Interest Entity, Primary Beneficiary [Member]
Accounts Receivable and Loans Textuals
Card Member loans	25,219	32,230
Global Consumer Services Group [Member]
Accounts Receivable and Loans Textuals
Card Member loans	57,538	73,266
Global Consumer Services Group [Member] \| Variable Interest Entity, Primary Beneficiary [Member]
Accounts Receivable and Loans Textuals
Card Member loans	25,200	32,200
Global Commercial Services [Member]
Accounts Receivable and Loans Textuals
Card Member loans	$ 12,068	$ 14,115

Accounts Receivable and Loans.

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Reserves for Losses, Other Loans.

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Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for loans and leases covered under loss sharing agreements.

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Amount before allowance and after deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements.

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Amount, after allowance for credit loss, of financing receivable. Excludes financing receivable covered under loss sharing agreement.

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