Supplemental Statement of Cash Flows Information 2 (Details) (USD $) In Millions, unless otherwise specified	6 Months Ended
	Sep. 30, 2014	Sep. 30, 2013
Supplemental Cash Flow Information [Abstract]
Interest payments, net	$ 40	$ 31
Income taxes paid, net	181	246
Excess tax benefits from share-based incentive awards included in financing activities from continuing operations	3	3
Share-based incentive awards, Non-cash financing activities	42	46
Withholding taxes on share-based incentive awards, Non-cash financing activities	27	27
Discretionary stock contributions to CA, Inc. Savings Harvest Plan, Non-cash financing activities	26	28
Treasury common shares issued in connection with Employee Stock Purchase Plan, Non-cash financing activities	$ 3	$ 2