Investments Proportional (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended								9 Months Ended
	Sep. 29, 2012		Sep. 30, 2012		Sep. 30, 2011		Sep. 24, 2011		Sep. 29, 2012		Sep. 30, 2012		Sep. 24, 2011
Schedule of Equity Method Investments [Line Items]
Equity income in MillerCoors	$ 132.0						$ 99.4		$ 436.5				$ 372.4
MillerCoors
Schedule of Equity Method Investments [Line Items]
Net income attributable to MillerCoors	306.9		306.9	[1]	176.4	[1]	176.4		1,020.5		1,020.5	[1]	809.8	[1]
MCBC economic interest	42.00%						42.00%		42.00%				42.00%
MCBC proportionate share of MillerCoors net income	128.9						74.1		428.6				340.1
Amortization of the difference between MCBC contributed cost basis and proportional share of the underlying equity in the net assets of MillerCoors	1.2	[2]					27.7	[2]	3.1	[2]			32.6	[2]
Share-based compensation adjustment	1.9	[3]					(2.4)	[3]	4.8	[3]			(0.3)	[3]
Equity income in MillerCoors	132.0						99.4		436.5				372.4
Equity Method Investment, Difference Between Carrying Amount and Underlying Equity	585								585
Basis Difference Relating To Millercoors Assumption Of Liabilities As Part Of Under Funded Multi Employer Pension Plan	$ 35.0

[1] Results for the three months and nine months ended September 30, 2012, include special charges of $18.7 million and $16.4 million, respectively, primarily due to the write-down of assets related to discontinuing the production of the Home Draft package in the U.S. Results for the three months and nine months ended September 30, 2011, include special charges of $60.0 million for a write-down in the value of the Sparks brand and a $50.9 million charge resulting from the planned assumption of the Milwaukee Brewery Worker's Pension Plan, an under-funded multi-employer pension plan.

[2] Our net investment in MillerCoors is based on the carrying values of the net assets contributed to the joint venture which is less than our proportional share of underlying equity (42%) of MillerCoors (contributed by both Coors Brewing Company ("CBC") and Miller Brewing Company ("Miller")) by approximately $585 million as of September 29, 2012. This difference, with the exception of goodwill and land, is amortized as additional equity income over the remaining useful lives of the contributed long-lived amortizing assets. The current basis difference combined with the $35.0 million recorded in 2008 and 2009 related to differences resulting from accounting policy elections must be considered to reconcile MillerCoors equity to our investment in MillerCoors.

[3] The net adjustment is to record all share-based compensation associated with pre-existing equity awards to be settled in Class B common stock held by former employees now employed by MillerCoors and to eliminate all share-based compensation impacts related to pre-existing SABMiller plc equity awards held by former Miller employees now employed by MillerCoors. As of the end of the second quarter of 2011, the share-based awards granted to former CBC employees now employed by MillerCoors became fully vested. As such, no further adjustments will be recorded related to these awards. We are still recording adjustments to eliminate the impacts related to the pre-existing SABMiller plc equity awards, which represent the amounts recorded in 2012.