Condensed Consolidated Statements of Comprehensive Income (USD $) In Millions, unless otherwise specified	3 Months Ended		6 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Statement of Comprehensive Income [Abstract]
Net Income	$ 404	$ 401	$ 828	$ 781
Other Comprehensive Income, Net of Tax [Abstract]
Foreign currency translation adjustments, net of income tax expense (benefit) of $22, ($2), $24 and $2	100	71	39	30
Unrealized gains (losses) on cash flow hedges, net of income tax expense of nil, nil, nil and nil	(2)	2	(1)	2
Retirement-related benefit plans, net of income tax expense of $3, $2, $7 and $5	4	3	11	9
Other Comprehensive Income, Net of Tax	102	76	49	41
Comprehensive Income	$ 506	$ 477	$ 877	$ 822