Consolidated Statements of Income - USD ($) shares in Millions, $ in Millions	3 Months Ended				6 Months Ended
	Jun. 30, 2015		Jun. 30, 2014		Jun. 30, 2015		Jun. 30, 2014
Non-interest revenues
Discount revenue	$ 4,946		$ 4,919		$ 9,606		$ 9,539
Net card fees	667		687		1,334		1,361
Travel commissions and fees	95		500		184		923
Other commissions and fees	632		624		1,251		1,242
Other	521		585		989		1,086
Total non-interest revenues	6,861		7,315		13,364		14,151
Interest income
Interest on loans	1,776		1,696		3,571		3,407
Interest and dividends on investment securities	41		45		82		91
Deposits with banks and other	20		18		41		37
Total interest income	1,837		1,759		3,694		3,535
Interest expense
Deposits	109		91		212		185
Long-term debt and other	305		352		612		697
Total interest expense	414		443		824		882
Net interest income	1,423		1,316		2,870		2,653
Total revenues net of interest expense	8,284		8,631		16,234		16,804
Provisions for losses
Charge card	165		183		339		398
Card Member loans	285		282		520		532
Other	17		24		28		44
Total provisions for losses	467		489		887		974
Total revenues net of interest expense after provisions for losses	7,817		8,142		15,347		15,830
Expenses
Marketing and promotion	761		959		1,370		1,546
Card Member rewards	1,799		1,773		3,439		3,355
Card Member services and other	242		192		503		414
Salaries and employee benefits	1,250		1,658		2,555		3,198
Other, net	1,535		1,248		2,934		2,797
Total expenses	5,587		5,830		10,801		11,310
Pretax income	2,230		2,312		4,546		4,520
Income tax provision	757		783		1,548		1,559
Net income	$ 1,473		$ 1,529		$ 2,998		$ 2,961
Earnings Per Common Share, Basic [Abstract]
Income from continuing operations attributable to common shareholders	$ 1.43	[1]	$ 1.44	[1]	$ 2.92	[2]	$ 2.78	[2]
Earnings Per Common Share, Diluted [Abstract]
Income from continuing operations attributable to common shareholders	$ 1.42	[1]	$ 1.43	[1]	$ 2.9	[2]	$ 2.77	[2]
Average common shares outstanding for earnings per common share:
Basic	1,009	[1]	1,052	[1]	1,013	[2]	1,056	[2]
Diluted	1,013	[1]	1,058	[1]	1,018	[2]	1,062	[2]
Cash dividends declared per common share	$ 0.29	[1]	$ 0.26	[1]	$ 0.55	[2]	$ 0.49	[2]

[1] Represents net income less ( i ) earnings allocated to participating share awards of $ 11 million and $ 12 million for the three months ended June 30, 2015 and 2014 , respect ively, and (ii) dividends on preferred shares of $20 million and nil for the three months ended June 30, 2015

[2] Represents net income less ( i ) earnings allocate d to participating share awards of $ 22 million and $ 24 million for the six months ended June 30 , 2015 and 2014 , respectively, and (ii) di vidends on preferred shares of $20 million and nil for the six months ended June 30, 2015 and 2014, respectively.