Segment Information 1 (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Jun. 30, 2013		Jun. 30, 2012
Segment information
Revenue	$ 1,128		$ 1,145
Income before interest and income taxes	228		381
Reconciliation of segment profit to income before income taxes
Segment profit	228		381
Software development costs capitalized	(23)		(36)
Share-based compensation expense	20		23
Other (gains) expenses, net	118	[1]	(6)	[2]
Interest expense, net	11		11
Income before income taxes	217		370
Purchased Software Products [Member]
Reconciliation of segment profit to income before income taxes
Amortization of intangible ssets	28		27
Other Intangible Assets [Member]
Reconciliation of segment profit to income before income taxes
Amortization of intangible ssets	14		14
Internally Developed Software Products [Member]
Reconciliation of segment profit to income before income taxes
Amortization of intangible ssets	41		37
Mainframe Solutions [Member]
Segment information
Revenue	619		628
Expenses	242		261
Income before interest and income taxes	377		367
Segment operating margin	61.00%		58.00%
Depreciation	13		16
Reconciliation of segment profit to income before income taxes
Segment profit	377		367
Enterprise Solutions [Member]
Segment information
Revenue	411		426
Expenses	370		357
Income before interest and income taxes	41		69
Segment operating margin	10.00%		16.00%
Depreciation	9		11
Reconciliation of segment profit to income before income taxes
Segment profit	41		69
Services [Member]
Segment information
Revenue	98		91
Expenses	90		87
Income before interest and income taxes	8		4
Segment operating margin	8.00%		4.00%
Depreciation	0		0
Reconciliation of segment profit to income before income taxes
Segment profit	8		4
Total Reportable Segments [Member]
Segment information
Revenue	1,128		1,145
Expenses	702		705
Income before interest and income taxes	426		440
Segment operating margin	38.00%		38.00%
Depreciation	22		27
Reconciliation of segment profit to income before income taxes
Segment profit	$ 426		$ 440

[1] Other (gains) expenses, net consists of $120 million of costs associated with the Fiscal 2014 Plan, certain foreign exchange derivative hedging gains and losses, and other miscellaneous costs.

[2] Other (gains) expenses, net consists of certain foreign exchange derivative hedging gains and losses, and other miscellaneous costs.