Supplemental Statement of Cash Flows Information (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Mar. 31, 2013	Mar. 31, 2012	Mar. 31, 2011
Supplemental Statement of Cash Flows Information (Textual) [Abstract]
Interest payments, net	$ 61	$ 61	$ 72
Income taxes paid, net	333	420	222
Excess tax benefits from options exercised included in financing activities from continuing operations	6	3
Excess tax benefits from options exercised included in financing activities from continuing operations			less than $1 million
Assets acquired under capital leases	9	5	9
Share-based incentive awards	64	55	64
Withholding taxes on share-based incentive awards	34	26	27
Discretionary stock contributions to CA, Inc. Savings Harvest Plan	29	13	25
Treasury stock issued under Employee Stock Purchase Plan	$ 6