Segment Information Reportable Segments and Reconciliation to Consolidated Net Income (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended				12 Months Ended
	Mar. 31, 2015		Mar. 31, 2014		Mar. 31, 2015	Mar. 31, 2014
Segment Reporting Disclosure [Line Items]
Net sales	$ 22,717		$ 19,741
Segment operating expenses	22,462		19,595
Income (loss) from operations	255		146
Stock-based compensation	(407)		(321)		(1,582)	(1,226)
Other operating income (expense), net	(44)		(35)
Total non-operating income (expense)	(234)		(26)
Provision for income taxes	(71)		(73)
Equity-method investment activity, net of tax	(7)		61
Net income (loss)	(57)		108		(405)	299
Operating Segments
Segment Reporting Disclosure [Line Items]
Net sales	22,717		19,741
Segment operating expenses	22,011	[1]	19,239	[1]
Income (loss) from operations	706		502
North America | Operating Segments
Segment Reporting Disclosure [Line Items]
Net sales	13,406		10,808
Segment operating expenses	12,889	[1]	10,518	[1]
Income (loss) from operations	517		290
International | Operating Segments
Segment Reporting Disclosure [Line Items]
Net sales	7,745		7,883
Segment operating expenses	7,821	[1]	7,916	[1]
Income (loss) from operations	(76)		(33)
AWS | Operating Segments
Segment Reporting Disclosure [Line Items]
Net sales	1,566		1,050
Segment operating expenses	1,301	[1]	805	[1]
Income (loss) from operations	$ 265		$ 245

[1] Excludes stock-based compensation and “Other operating expense (income), net” which are not allocated to segments.