Net Sales of Similar Products and Services (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended																12 Months Ended
	Dec. 31, 2011		Sep. 30, 2011		Jun. 30, 2011		Mar. 31, 2011		Dec. 31, 2010		Sep. 30, 2010		Jun. 30, 2010		Mar. 31, 2010		Dec. 31, 2011		Dec. 31, 2010		Dec. 31, 2009
Revenue from External Customer [Line Items]
Net Sales	$ 17,431	[1]	$ 10,876	[1]	$ 9,913	[1]	$ 9,857	[1]	$ 12,948	[1]	$ 7,560	[1]	$ 6,566	[1]	$ 7,131	[1]	$ 48,077		$ 34,204		$ 24,509
Media
Revenue from External Customer [Line Items]
Net Sales																	17,779		14,888		12,774
Electronics and other general merchandise
Revenue from External Customer [Line Items]
Net Sales																	28,712		18,363		11,082
Other
Revenue from External Customer [Line Items]
Net Sales																	$ 1,586	[2]	$ 953	[2]	$ 653	[2]

[1] The sum of quarterly amounts, including per share amounts, may not equal amounts reported for year-to-date periods. This is due to the effects of rounding and changes in the number of weighted-average shares outstanding for each period.

[2] Includes non-retail activities, such as AWS, miscellaneous marketing and promotional activities, other seller sites, and our co-branded credit card agreements.