Goodwill, Capitalized Software and Other Intangible Assets 1 (Details) (USD $) In Millions, unless otherwise specified	Dec. 31, 2013	Mar. 31, 2013
Capitalized software and other intangible assets
Gross amortizable assets	$ 8,099	$ 7,941
Less: Fully amortized assets	6,005	5,825
Remaining amortizable assets	2,094	2,116
Accumulated amortization on remaining amortizable assets	965	885
Net assets	1,129	1,231
Purchased Software Products [Member]
Capitalized software and other intangible assets
Gross amortizable assets	5,693	5,597
Less: Fully amortized assets	4,797	4,735
Remaining amortizable assets	896	862
Accumulated amortization on remaining amortizable assets	334	309
Net assets	562	553
Internally Developed Software Products [Member]
Capitalized software and other intangible assets
Gross amortizable assets	1,560	1,528
Less: Fully amortized assets	722	661
Remaining amortizable assets	838	867
Accumulated amortization on remaining amortizable assets	391	327
Net assets	447	540
Other Intangible Assets [Member]
Capitalized software and other intangible assets
Gross amortizable assets	846	816
Less: Fully amortized assets	486	429
Remaining amortizable assets	360	387
Accumulated amortization on remaining amortizable assets	240	249
Net assets	$ 120	$ 138