Shareholders' Equity (Details) (USD $) In Millions, except Share data, unless otherwise specified	3 Months Ended			12 Months Ended
	Mar. 24, 2012	Mar. 19, 2011		Dec. 25, 2010
Repurchase Of Shares Of The Company's Common Stock [Line Items]
Shares Repurchased	1,219,000	2,873,000	[1]
Dollar Value of Shares Repurchased	$ 78	$ 142	[1]
Remaining dollar value of shares that may be repurchased	860
Value Of Share Repurchases In Current Fiscal Quarter But With Settlement Dates In Subsequent Fiscal Quarter		9		19
Share Repurchases In Current Fiscal Quarter But With Settlement Dates In Subsequent Fiscal Quarter		200,000		400,000
March 2010 [Member]
Repurchase Of Shares Of The Company's Common Stock [Line Items]
Expiration Date	March 2011
Shares Repurchased	0	2,873,000
Dollar Value of Shares Repurchased	0	142
Remaining dollar value of shares that may be repurchased	0
January 2011 [Member]
Repurchase Of Shares Of The Company's Common Stock [Line Items]
Expiration Date	June 2012
Shares Repurchased	1,219,000	0
Dollar Value of Shares Repurchased	78	0
Remaining dollar value of shares that may be repurchased	110
November 2011 [Member]
Repurchase Of Shares Of The Company's Common Stock [Line Items]
Expiration Date	May 2013
Shares Repurchased	0	0
Dollar Value of Shares Repurchased	0	0
Remaining dollar value of shares that may be repurchased	$ 750

[1] Amount excludes the effect of $19 million in share repurchases (0.4 million shares) with trade dates prior to the 2010 fiscal year end but cash settlement dates subsequent to the 2010 fiscal year end and includes the effect of $9 million in share repurchases (0.2 million shares) with trade dates prior to March 19, 2011 but with settlement dates subsequent to March 19, 2011.