Consolidated Statements of Income (USD $) In Millions, except Per Share data	3 Months Ended				9 Months Ended
	Sep. 30, 2011		Sep. 30, 2010		Sep. 30, 2011		Sep. 30, 2010
Non-interest revenues
Discount revenue	$ 4,218		$ 3,761		$ 12,398		$ 10,863
Net card fees	556		527		1,638		1,568
Travel commissions and fees	480		483		1,457		1,302
Other commissions and fees	604		515		1,717		1,512
Other	534		503		1,546		1,414
Total non-interest revenues	6,392		5,789		18,756		16,659
Interest income
Interest and fees on loans	1,653		1,675		4,883		5,107
Interest and dividends on investment securities	68		103		255		345
Deposits with banks and other	33		16		71		45
Total interest income	1,754		1,794		5,209		5,497
Interest expense
Deposits	127		141		395		406
Short-term borrowings	5		0		6		2
Long-term debt and other	443		469		1,344		1,410
Total interest expense	575		610		1,745		1,818
Net interest income	1,179		1,184		3,464		3,679
Total revenues net of interest expense	7,571		6,973		22,220		20,338
Provisions for losses
Charge card	174		89		533		412
Cardmember loans	48		262		104		1,490
Other	27		22		66		66
Total provisions for losses	249		373		703		1,968
Total revenues net of interest expense after provisions for losses	7,322		6,600		21,517		18,370
Expenses
Marketing, promotion, rewards and cardmember services	2,511		2,275		7,542		6,405
Salaries and employee benefits	1,598		1,354		4,715		3,996
Professional services	690		701		2,098		1,898
Other, net	812		630		1,954		1,584
Total	5,611		4,960		16,309		13,883
Pretax income from continuing operations	1,711		1,640		5,208		4,487
Income tax provision	476		547		1,501		1,492
Income from continuing operations	1,235		1,093		3,707		2,995
Income from discontinued operations, net of tax					36		0
Net income	$ 1,235		$ 1,093		$ 3,743		$ 2,995
Earnings Per Share, Basic [Abstract]
Income from continuing operations attributable to common shareholders	$ 1.04		$ 0.91		$ 3.09	[1]	$ 2.49	[1]
Income from discontinued operations, net of tax					$ 0.03	[1]	$ 0	[1]
Net income attributable to common shareholders	$ 1.04	[2]	$ 0.91	[2]	$ 3.12	[1]	$ 2.49	[1]
Earnings Per Share, Diluted [Abstract]
Income from continuing operations attributable to common shareholders	$ 1.03		$ 0.90		$ 3.08	[1]	$ 2.47	[1]
Income from discontinued operations, net of tax					$ (0.03)	[1]	$ 0	[1]
Net income attributable to common shareholders	$ 1.03	[2]	$ 0.90	[2]	$ 3.11	[1]	$ 2.47	[1]
Average common shares outstanding for earnings per common share:
Basic	1,175		1,193		1,184		1,189
Diluted	1,181		1,199		1,191		1,195
Common Stock Dividends Per Share Declared [Abstract]
Cash dividends declared per common share	$ 0.18		$ 0.18		$ 0.54		$ 0.54

[1] Represents income from continuing operations or net income, as applicable, less earnings allocated to participating share awards and other items of $44 million and $38 million for the nine months ended September 30, 2011 and 2010, respectively.

[2] Represents net income less earnings allocated to participating share awards and other items of $15 million and $13 million for the three months ended September 30, 2011 and 2010, respectively.