Goodwill Capitalized Software and Other Intangible Assets 1 (Details) (USD $) In Millions, unless otherwise specified	Dec. 31, 2011	Mar. 31, 2011
Capitalized software and other intangible assets
Total capitalized software and other intangible assets, Gross	$ 7,763	$ 7,417
Total capitalized software and other intangible assets, Accumulated Amortization	6,337	6,133
Capitalized software and other intangible assets, net	1,426	1,284
Intangible Assets Not Fully Amortized [Member] | Purchased software products [Member]
Capitalized software and other intangible assets
Total capitalized software and other intangible assets, Gross	897	768
Total capitalized software and other intangible assets, Accumulated Amortization	203	198
Capitalized software and other intangible assets, net	694	570
Intangible Assets Not Fully Amortized [Member] | Internally developed software products [Member]
Capitalized software and other intangible assets
Total capitalized software and other intangible assets, Gross	771	693
Total capitalized software and other intangible assets, Accumulated Amortization	242	205
Capitalized software and other intangible assets, net	529	488
Intangible Assets Not Fully Amortized [Member] | Other intangible assets subject to amortization [Member]
Capitalized software and other intangible assets
Total capitalized software and other intangible assets, Gross	409	652
Total capitalized software and other intangible assets, Accumulated Amortization	206	440
Capitalized software and other intangible assets, net	203	212
Intangible Assets Not Fully Amortized [Member] | Other intangible assets not subject to amortization [Member]
Capitalized software and other intangible assets
Total capitalized software and other intangible assets, Gross		14
Capitalized software and other intangible assets, net		14
Intangible Assets Not Fully Amortized [Member] | Capitalized software and other intangible assets [Member]
Capitalized software and other intangible assets
Total capitalized software and other intangible assets, Gross	2,077	2,127
Total capitalized software and other intangible assets, Accumulated Amortization	651	843
Capitalized software and other intangible assets, net	$ 1,426	$ 1,284