Fair Values (Details 2) (USD $) In Millions, unless otherwise specified	Jun. 30, 2012	Dec. 31, 2011	Jun. 30, 2011	Dec. 31, 2010
Financial Assets For Which Carrying Values Equal Or Approximate Fair Value[ Abstract]
Cash and cash equivalents	$ 22,072	$ 24,893	$ 23,082	$ 16,356
Liabilities Carried At Other Than Fair Value [Abstract]
Certificates of deposit	9,947
Long-term Debt	55,953	59,570
Fair Values (Textuals) [Abstract]
Accounts receivable, less reserves	41,148	40,452
Cardmember loans, net	59,432	60,747
Variable Interest Enterprise [Member]
Liabilities Carried At Other Than Fair Value [Abstract]
Long-term Debt	15,976	20,856
Fair Values (Textuals) [Abstract]
Accounts receivable, less reserves	7,200
Carrying Value [Member]
Financial Assets For Which Carrying Values Equal Or Approximate Fair Value[ Abstract]
Cash and cash equivalents	22
Other assets	46
Assets Carried At Other Than Fair Value [Abstract]
Loans, net	60
Financial Liabilities:
Liabilities for which carrying values equal or approximate fair value	53
Liabilities Carried At Other Than Fair Value [Abstract]
Certificates of deposit	10
Long-term Debt	56
Level 1 [Member]
Financial Assets For Which Carrying Values Equal Or Approximate Fair Value[ Abstract]
Cash and cash equivalents	21
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 For Which Carrying Values Equal Or Approximate Fair Value[ Abstract]
Cash and cash equivalents	1
Other assets	46
Assets Carried At Other Than Fair Value [Abstract]
Loans, net	0
Financial Liabilities:
Liabilities for which carrying values equal or approximate fair value	53
Liabilities Carried At Other Than Fair Value [Abstract]
Certificates of deposit	10
Long-term Debt	59
Level 3 [Member]
Financial Assets For Which Carrying Values Equal Or Approximate Fair Value[ Abstract]
Cash and cash equivalents	0
Other assets	0
Assets Carried At Other Than Fair Value [Abstract]
Loans, net	61
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 For Which Carrying Values Equal Or Approximate Fair Value[ Abstract]
Cash and cash equivalents	22
Other assets	46
Assets Carried At Other Than Fair Value [Abstract]
Loans, net	61
Financial Liabilities:
Liabilities for which carrying values equal or approximate fair value	53
Liabilities Carried At Other Than Fair Value [Abstract]
Certificates of deposit	10
Long-term Debt	59
Fair Value [Member] | Variable Interest Enterprise [Member]
Liabilities Carried At Other Than Fair Value [Abstract]
Long-term Debt	16,200
Fair Values (Textuals) [Abstract]
Cardmember loans, net	$ 31,100