Long-Lived Assets 3 (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Mar. 31, 2012	Mar. 31, 2011	Mar. 31, 2010
Depreciation and amortization expense
Depreciation	$ 111	$ 114	$ 105
Depreciation and Amortization, Total	401	379	292
Purchased Software [Member]
Depreciation and amortization expense
Amortization of Intangible Assets	103	88	49
Internally developed software products [Member]
Depreciation and amortization expense
Amortization of Intangible Assets	122	104	84
Other Intangible Assets [Member]
Depreciation and amortization expense
Amortization of Intangible Assets	$ 65	$ 73	$ 54