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, 2014		Mar. 31, 2013		Mar. 31, 2014	Mar. 31, 2013
Segment Reporting Disclosure [Line Items]
Net sales	$ 19,741		$ 16,070
Segment operating expenses	19,595		15,889
Income from operations	146		181
Stock-based compensation	(321)		(229)		(1,226)	(901)
Other operating income (expense), net	(35)		(31)
Total non-operating income (expense)	(26)		(100)
Benefit (provision) for income taxes	(73)		18
Equity-method investment activity, net of tax	61		(17)
Net income	108		82		299	(87)
Operating Segments
Segment Reporting Disclosure [Line Items]
Net sales	19,741		16,070
Segment operating expenses	19,239	[1]	15,629	[1]
Income from operations	502		441
Operating Segments | North America
Segment Reporting Disclosure [Line Items]
Net sales	11,858		9,391
Segment operating expenses	11,296	[1]	8,934	[1]
Income from operations	562		457
Operating Segments | International
Segment Reporting Disclosure [Line Items]
Net sales	7,883		6,679
Segment operating expenses	7,943	[1]	6,695	[1]
Income from operations	$ (60)		$ (16)

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