Goodwill, Capitalized Software and Other Intangible Assets 1 (Details) - USD ($) $ in Millions	Dec. 31, 2015	Mar. 31, 2015
Capitalized software and other intangible assets
Gross amortizable assets	$ 8,398	$ 8,039
Less: Fully amortized assets	6,465	6,250
Remaining amortizable assets	1,933	1,789
Accumulated amortization on remaining amortizable assets	1,067	1,058
Net assets	866	731
Purchased Software Products
Capitalized software and other intangible assets
Gross amortizable assets	5,987	5,717
Less: Fully amortized assets	4,863	4,859
Remaining amortizable assets	1,124	858
Accumulated amortization on remaining amortizable assets	513	413
Net assets	611	445
Internally Developed Software Products
Capitalized software and other intangible assets
Gross amortizable assets	1,485	1,486
Less: Fully amortized assets	994	835
Remaining amortizable assets	491	651
Accumulated amortization on remaining amortizable assets	341	414
Net assets	150	237
Other Intangible Assets
Capitalized software and other intangible assets
Gross amortizable assets	926	836
Less: Fully amortized assets	608	556
Remaining amortizable assets	318	280
Accumulated amortization on remaining amortizable assets	213	231
Net assets	$ 105	$ 49