Income Taxes (Narrative) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended		6 Months Ended		3 Months Ended			3 Months Ended		6 Months Ended
	Sep. 28, 2012	Sep. 30, 2011	Sep. 28, 2012	Sep. 30, 2011	Sep. 28, 2012 Valuation Allowance On State Credits [Member]	Dec. 30, 2011 Veritas 02-05 Exam Cycle [Member]	Jan. 15, 2010 Veritas 02-05 Exam Cycle [Member]	Sep. 28, 2012 Lapse Of Statues Of Limitations [Member]	Sep. 30, 2011 Lapse Of Statues Of Limitations [Member]	Sep. 28, 2012 Lapse Of Statues Of Limitations [Member]	Sep. 30, 2011 Lapse Of Statues Of Limitations [Member]	Sep. 28, 2012 Forecasted Rate [Member]	Sep. 30, 2011 Forecasted Rate [Member]	Sep. 28, 2012 Minimum [Member] Possible Gross Unrecognized Tax Benefits Within Next Twelve Months [Member]	Sep. 28, 2012 Maximum [Member] Possible Gross Unrecognized Tax Benefits Within Next Twelve Months [Member]
Income Taxes [Line Items]
Effective tax rate	29.00%	27.00%	28.00%	26.00%								29.00%	29.00%
Income Tax Expense (Benefit)	$ 80	$ 67	$ 145	$ 134	$ 9	$ (52)		$ (3)	$ (5)	$ (6)	$ (12)
Prior year adjustment			3
Decrease of unrecognized tax benefits as a result of tax court decision	5		5
Original IRS Assessment							80
Significant change in unrecognized tax benefits is reasonably possible amount of unrecorded benefit	15		15											160	310
Amount on deposit with the IRS pertaining to US Tax matters in the Veritas 2002-2005 and the Symantec 2005-2008 audit cycles	$ 184		$ 184