Consolidated Statements of Stockholders' Equity (USD $) In Millions	Total	Common Stock	Additional Paid-in Capital	Retained Earnings	Accumulated Other Comprehensive Loss	Treasury Stock
Beginning balance at Mar. 31, 2012	$ 5,397	$ 59	$ 3,491	$ 4,865	$ (108)	$ (2,910)
Net income	955			955
Other comprehensive loss	(47)				(47)
Comprehensive income	908
Share-based compensation	78		78
Dividends declared	(463)			(463)
Release of restricted stock, exercise of common stock options, ESPP and other items	25		(101)			126
Accelerated share repurchase	0		125			(125)
Treasury stock purchased	(495)					(495)
Ending balance at Mar. 31, 2013	5,450	59	3,593	5,357	(155)	(3,404)
Net income	914			914
Other comprehensive loss	(16)				(16)
Comprehensive income	898
Share-based compensation	82		82
Dividends declared	(453)			(453)
Release of restricted stock, exercise of common stock options, ESPP and other items	98		(65)			163
Treasury stock purchased	(505)					(505)
Ending balance at Mar. 31, 2014	5,570	59	3,610	5,818	(171)	(3,746)
Net income	846			846
Other comprehensive loss	(247)				(247)
Comprehensive income	599
Share-based compensation	87		87
Dividends declared	(444)			(444)
Release of restricted stock, exercise of common stock options, ESPP and other items	28		(66)	1		93
Treasury stock purchased	(215)					(215)
Ending balance at Mar. 31, 2015	$ 5,625	$ 59	$ 3,631	$ 6,221	$ (418)	$ (3,868)