CONDENSED CONSOLIDATED BALANCE SHEETS (PARENTHETICAL) (USD $) In Millions, except Per Share data	Sep. 24, 2011	Dec. 25, 2010
Preferred stock, non-voting, authorized shares	25.0	25.0
Preferred stock, non-voting, issued shares	0	0
Class B common stock held in treasury	6.3	0
Class A common stock, voting
Common stock, par value	$ 0.01	$ 0.01
Common stock, authorized shares	500.0	500.0
Common stock, issued shares	2.6	2.6
Common stock, outstanding shares	2.6	2.6
Class B common stock, non-voting
Common stock, par value	$ 0.01	$ 0.01
Common stock, authorized shares	500.0	500.0
Common stock, issued shares	162.6	162.0
Class A exchangeable shares
Exchangeable shares, issued shares	2.9	3.0
Exchangeable shares, outstanding shares	2.9	3.0
Class B exchangeable shares
Exchangeable shares, issued shares	19.3	19.2
Exchangeable shares, outstanding shares	19.3	19.2