Earnings Per Share (Schedule Of Components Of Earnings Per Share) (Details) (USD $) In Millions, except Per Share data, unless otherwise specified	3 Months Ended				6 Months Ended
	Sep. 28, 2012		Sep. 30, 2011		Sep. 28, 2012		Sep. 30, 2011
Earnings Per Share [Line Items]
Net income	$ 193		$ 182		$ 365		$ 373
Net income per share attributable to Symantec Corporation stockholders-basic	$ 0.27		$ 0.24		$ 0.51		$ 0.50
Net income per share attributable to Symantec Corporation stockholders-diluted	$ 0.27		$ 0.24		$ 0.51		$ 0.49
Weighted average outstanding common shares attributable to Symantec Corporation stockholders-basic	702		745		709		750
Dilutive potential shares issuable from assumed exercise of stock options	2		3		2		4
Dilutive potential shares related to stock award plans	4		3		3		4
Total weighted-average shares outstanding attributable to Symantec Corporation stockholders-diluted	708		751		714		758
Conversion price for dilution	$ 19.12		$ 19.12		$ 19.12		$ 19.12
Warrant [Member]
Earnings Per Share [Line Items]
Conversion price for dilution	$ 27.3175		$ 27.3175		$ 27.3175		$ 27.3175
Anti-Dilutive Weighted-Average Stock Options [Member]
Earnings Per Share [Line Items]
Anti-dilutive weighted-average shares	26	[1]	33	[1]	26	[1]	31	[1]
Anti-Dilutive Weighted-Average Restricted Stock [Member]
Earnings Per Share [Line Items]
Anti-dilutive weighted-average shares	1	[1]	1	[1]		[1]		[1]

[1] For the periods presented, the effects of the warrants issued and the option purchased in connection with the Convertible Senior Notes were excluded because they have no impact on diluted earnings per share until our average stock price for the applicable period reaches $27.3175 per share and $19.12 per share, respectively