Fair Values (Details 2) (USD $) In Millions, unless otherwise specified	Mar. 31, 2012	Dec. 31, 2011	Mar. 31, 2011	Dec. 31, 2010
Financial Assets:
Cash and cash equivalents	$ 27,082	$ 24,893	$ 22,027	$ 16,356
Liabilities Carried At Other Than Fair Value [Abstract]
Certificates of deposit	11,081
Long-term Debt	56,844	59,570
Fair Values (Textuals) [Abstract]
Accounts receivable, less reserves	41,083	40,452
Cardmember loans, net	58,417	60,747
Variable Interest Enterprise [Member]
Liabilities Carried At Other Than Fair Value [Abstract]
Long-term Debt	17,477	20,856
Fair Values (Textuals) [Abstract]
Accounts receivable, less reserves	7,100	8,000
Cardmember loans, net	30,900	33,300
Carrying Value [Member]
Financial Assets:
Cash and cash equivalents	27
Other assets	45
Assets Carried At Other Than Fair Value [Abstract]
Loans, net	59
Financial Liabilities:
Liabilities for which carrying values equal or approximate fair value	54
Liabilities Carried At Other Than Fair Value [Abstract]
Certificates of deposit	11
Long-term Debt	57
Level 1 [Member]
Financial Assets:
Cash and cash equivalents	23
Other assets	0
Assets Carried At Other Than Fair Value [Abstract]
Loans, net	0
Financial Liabilities:
Liabilities for which carrying values equal or approximate fair value	0
Liabilities Carried At Other Than Fair Value [Abstract]
Certificates of deposit	0
Long-term Debt	0
Level 2 [Member]
Financial Assets:
Cash and cash equivalents	4
Other assets	45
Assets Carried At Other Than Fair Value [Abstract]
Loans, net	0
Financial Liabilities:
Liabilities for which carrying values equal or approximate fair value	54
Liabilities Carried At Other Than Fair Value [Abstract]
Certificates of deposit	11
Long-term Debt	60
Level 3 [Member]
Financial Assets:
Cash and cash equivalents	0
Other assets	0
Assets Carried At Other Than Fair Value [Abstract]
Loans, net	59
Financial Liabilities:
Liabilities for which carrying values equal or approximate fair value	0
Liabilities Carried At Other Than Fair Value [Abstract]
Certificates of deposit	0
Long-term Debt	0
Fair Value [Member]
Financial Assets:
Cash and cash equivalents	27
Other assets	45
Assets Carried At Other Than Fair Value [Abstract]
Loans, net	59
Financial Liabilities:
Liabilities for which carrying values equal or approximate fair value	54
Liabilities Carried At Other Than Fair Value [Abstract]
Certificates of deposit	11
Long-term Debt	60
Fair Value [Member] | Variable Interest Enterprise [Member]
Liabilities Carried At Other Than Fair Value [Abstract]
Long-term Debt	$ 17,700	$ 21,100