Stock Plans 10 (Details) (USD $) In Millions, except Per Share data, unless otherwise specified	12 Months Ended					12 Months Ended									6 Months Ended		12 Months Ended
	Mar. 31, 2013	Mar. 31, 2012	Mar. 31, 2011	Mar. 28, 2013	Mar. 31, 2013 2011 Incentive Plan [Member]	Mar. 31, 2013 2011 Incentive Plan Stock Options [Member]	Mar. 31, 2013 Stock Option Awards [Member]	Mar. 31, 2013 1-Year Performance Share Units [Member] Grant Date [Member]	Mar. 31, 2013 1-Year Performance Share Units [Member] First Anniversary [Member]	Mar. 31, 2013 1-Year Performance Share Units [Member] Second Anniversary [Member]	Mar. 31, 2013 Restricted Stock Awards [Member] Minimum [Member]	Mar. 31, 2013 Restricted Stock Awards [Member] Maximum [Member]	Mar. 31, 2013 Restricted Stock Units [Member] Minimum [Member]	Mar. 31, 2013 Restricted Stock Units [Member] Maximum [Member]	Dec. 31, 2012 Employee Stock Purchase Plan [Member]	Jun. 30, 2012 Employee Stock Purchase Plan [Member]	Dec. 31, 2012 Employee Stock Purchase Plan [Member]	Mar. 31, 2013 Employee Stock Purchase Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares originally available for grant					45	10
Expiration term from grant date						10 years	10 years
Stock option awards vesting per year							one-third
Award vesting period from grant date							3 years				2 years	3 years	2 years	3 years
PSU vesting percentage								34.00%	33.00%	33.00%
Percentage of stock closing price on last day of offer period that ESPP participants can purchase Company stock																	95.00%
Number of shares issued under Employee Stock Purchase Plan															0.2	0.1
Average price per share issued under Employee Stock Purchase Plan															$ 20.88	$ 25.74
Number of shares available for future issuances under Employee Stock Purchase Plan																		29.7
Stock Plans (Textual) [Abstract]
Tax benefit from share-based incentive awards deductible for tax purposes	$ 2	$ 4	$ 24
Closing price of Company's common stock				$ 25.18
Computation of expected life, Simplified method	The Company’s computation of expected life was determined based on the simplified method (the average of the vesting period and option term).
Total vesting date fair value of RSAs and RSUs released	$ 92	$ 73	$ 82