Debt Table (Details)	9 Months Ended							6 Months Ended	3 Months Ended		1 Months Ended				3 Months Ended		9 Months Ended			3 Months Ended			9 Months Ended																										3 Months Ended						9 Months Ended					0 Months Ended			3 Months Ended				3 Months Ended	9 Months Ended
	Sep. 28, 2013 USD ($)		Sep. 29, 2012 USD ($)	Dec. 29, 2012 USD ($)		Jun. 30, 2007 USD ($)	Jun. 15, 2012 Convertible Senior Unsecured Note Due 2013 €500 Million 0.0% [Member] EUR (€)	Sep. 29, 2012 Line of Credit [Member]	Jun. 25, 2011 Line of Credit [Member] Revolving Multicurrency Bank Credit Facility [Member]	Jun. 30, 2012 Line of Credit [Member] Revolving Multicurrency Bank Credit Facility [Member] USD ($)	Sep. 29, 2012 Revolving Credit [Member]	Sep. 28, 2013 Revolving Credit [Member] USD ($)	Sep. 28, 2013 Revolving Credit [Member] EUR (€)	Apr. 03, 2012 Revolving Credit [Member] USD ($)	Sep. 28, 2013 Senior Notes [Member] USD ($)	Sep. 29, 2012 Senior Notes [Member] USD ($)	Sep. 28, 2013 Senior Notes [Member] USD ($)	Sep. 29, 2012 Senior Notes [Member] USD ($)	May 03, 2012 Senior Notes [Member] USD ($)	Sep. 28, 2013 Senior Notes [Member] $575 million 2.5% convertible Senior Notes due 2013 USD ($)		Sep. 29, 2012 Senior Notes [Member] $575 million 2.5% convertible Senior Notes due 2013 USD ($)	Sep. 28, 2013 Senior Notes [Member] $575 million 2.5% convertible Senior Notes due 2013 USD ($)		Sep. 29, 2012 Senior Notes [Member] $575 million 2.5% convertible Senior Notes due 2013 USD ($)	Sep. 09, 2013 Senior Notes [Member] $575 million 2.5% convertible Senior Notes due 2013 USD ($)	Dec. 29, 2012 Senior Notes [Member] $575 million 2.5% convertible Senior Notes due 2013 USD ($)	Jun. 15, 2007 Senior Notes [Member] $575 million 2.5% convertible Senior Notes due 2013 USD ($)	Sep. 28, 2013 Senior Notes [Member] Convertible Senior Unsecured Note Due 2013 €500 Million 0.0% [Member] USD ($)		Dec. 29, 2012 Senior Notes [Member] Convertible Senior Unsecured Note Due 2013 €500 Million 0.0% [Member] USD ($)		Sep. 28, 2013 Senior Notes [Member] Canadian dollar ("CAD") 900 million 5.0% notes due 2015 USD ($)	Dec. 29, 2012 Senior Notes [Member] Canadian dollar ("CAD") 900 million 5.0% notes due 2015 USD ($)	Sep. 22, 2005 Senior Notes [Member] Canadian dollar ("CAD") 900 million 5.0% notes due 2015 USD ($)	Sep. 28, 2013 Senior Notes [Member] CAD 500 million 3.95% Series A notes due 2017 USD ($)	Dec. 29, 2012 Senior Notes [Member] CAD 500 million 3.95% Series A notes due 2017 USD ($)	Oct. 06, 2010 Senior Notes [Member] CAD 500 million 3.95% Series A notes due 2017 USD ($)	Sep. 28, 2013 Senior Notes [Member] $300 million 2.0% notes due 2017 USD ($)	Dec. 29, 2012 Senior Notes [Member] $300 million 2.0% notes due 2017 USD ($)	Sep. 28, 2013 Senior Notes [Member] $500 million 3.5% notes due 2022 USD ($)	Dec. 29, 2012 Senior Notes [Member] $500 million 3.5% notes due 2022 USD ($)	Sep. 28, 2013 Senior Notes [Member] $1.1 billion 5.0% notes due 2042 USD ($)	Dec. 29, 2012 Senior Notes [Member] $1.1 billion 5.0% notes due 2042 USD ($)	May 03, 2012 Senior Notes [Member] 5.0% Interest Rate, Maturing 2042 [Member] USD ($)	Sep. 22, 2005 Senior Notes [Member] 5.0% Interest Rate, Maturing 2042 [Member]	May 03, 2012 Senior Notes [Member] 2.0% Interest Rate, Maturing 2017 [Member] USD ($)	May 03, 2012 Senior Notes [Member] 3.5% Interest Rate, Maturing 2022 [Member] USD ($)	Sep. 28, 2013 Tranch 2 [Member] Term Loan Agreement [Member] USD ($)		Sep. 28, 2013 Tranch 2 [Member] Term Loan Agreement [Member] EUR (€)	Dec. 29, 2012 Tranch 2 [Member] Term Loan Agreement [Member] USD ($)		Apr. 03, 2012 Tranch 2 [Member] Term Loan Agreement [Member] EUR (€)	Sep. 29, 2012 Molson Coors Central Europe (MCCE) USD ($)	Jun. 15, 2012 Molson Coors Central Europe (MCCE) USD ($)	Jun. 15, 2012 Molson Coors Central Europe (MCCE) EUR (€)	Jun. 15, 2012 Molson Coors Central Europe (MCCE) Senior Notes [Member] USD ($)	Jun. 15, 2012 Molson Coors Central Europe (MCCE) Senior Notes [Member] EUR (€)	Jun. 15, 2012 Molson Coors Central Europe (MCCE) Convertible Debt [Member] USD ($)	Jun. 15, 2012 Molson Coors Central Europe (MCCE) Convertible Debt [Member] EUR (€)	Jun. 15, 2012 Molson Coors Central Europe (MCCE) Convertible Debt [Member] Zero Coupon Senior Unsecured Note [Member] USD ($)	Sep. 28, 2013 Molson Coors Central Europe (MCCE) Convertible Debt [Member] Zero Coupon Senior Unsecured Note [Member] USD ($)	Sep. 28, 2013 Molson Coors Central Europe (MCCE) Convertible Debt [Member] Zero Coupon Senior Unsecured Note [Member] EUR (€)	Aug. 13, 2013 Molson Coors Central Europe (MCCE) Convertible Debt [Member] Zero Coupon Senior Unsecured Note [Member] EUR (€)	Jun. 15, 2012 Molson Coors Central Europe (MCCE) Convertible Debt [Member] Zero Coupon Senior Unsecured Note [Member] EUR (€)	Sep. 28, 2013 Equity conversion feature of debt Molson Coors Central Europe (MCCE) Convertible Debt [Member] Zero Coupon Senior Unsecured Note [Member] USD ($)	Sep. 28, 2013 Equity conversion feature of debt Molson Coors Central Europe (MCCE) Convertible Debt [Member] Zero Coupon Senior Unsecured Note [Member] USD ($)	Aug. 13, 2013 Equity conversion feature of debt Molson Coors Central Europe (MCCE) Convertible Debt [Member] Zero Coupon Senior Unsecured Note [Member] USD ($)	Aug. 13, 2013 Equity conversion feature of debt Molson Coors Central Europe (MCCE) Convertible Debt [Member] Zero Coupon Senior Unsecured Note [Member] EUR (€)	Sep. 28, 2013 Fair Value, Inputs, Level 3 [Member] USD ($)	Aug. 13, 2013 Fair Value, Inputs, Level 3 [Member] USD ($)	Dec. 29, 2012 Fair Value, Inputs, Level 3 [Member] USD ($)	Jun. 15, 2012 Fair Value, Inputs, Level 3 [Member] Debt [Member] Molson Coors Central Europe (MCCE) EUR (€)
Debt Instrument [Line Items]
Unrealized Gain (Loss) on Derivatives																																																																			$ 20,300,000	$ (6,500,000)
Repayments of Long-term Debt																																																	71,800,000		53,700,000
Total long-term debt (including current portion) before unamortized discounts and other																				0	[1]		0	[1]			575,000,000		60,800,000	[2]	668,700,000	[2]	873,300,000	902,700,000		485,200,000	501,500,000		300,000,000	300,000,000	500,000,000	500,000,000	1,100,000,000	1,100,000,000					0	[3]		123,900,000	[3]												510,900,000
Proceeds from Convertible Debt																										2,600,000
Impact of Stock Received under Purchased Call Options Stock Price on Diluted EPS High																				$ 66.13			$ 66.13
Other long-term debt	400,000			500,000
Commercial Paper Outstanding, Amount	391,100,000
Debt Instrument, Term								4 years	4 years		1 year
Credit facilities	0	[4]		0	[4]							162,300,000
Less: unamortized debt discounts and other	(5,400,000)			(17,400,000)
Total long-term debt (including current portion)	3,314,300,000			4,654,900,000																																													123,800,000		93,700,000
Derivative Financial Instruments, Liabilities, Fair Value Disclosure																																																																					14,400,000	10,900,000	0	14,400,000	7,900,000
Noncash or Part Noncash Acquisition, Debt Assumed																																																							645,900,000					645,900,000	511,100,000
Current portion of long-term debt	(60,800,000)			(1,232,400,000)																																																											(60,800,000)	(44,900,000)
Total long-term debt	3,253,500,000			3,422,500,000
Short-term debt	577,500,000			13,200,000
Current portion of long-term debt and short-term borrowings	638,300,000			1,245,600,000
Debt instrument, face amount						575,000,000							150,000,000						1,900,000,000									575,000,000							900,000,000			500,000,000							1,100,000,000		300,000,000	500,000,000						120,000,000												500,000,000
Debt instrument, interest rate percentage																				2.50%			2.50%					2.50%										3.95%							5.00%	5.00%	2.00%	3.50%															0.00%	0.00%
Calculation of Debt Premium Conversion Price, Period Following Maturity Date																							25 days
Proceeds from Call Options	2,600,000		0																				2,600,000
Debt Instrument, Principal Amount, Per Share																												1,000
Debt Instrument, Convertible Conversion Price Per Share																				$ 51.8284			$ 51.8284					$ 54.76
Percentage of Premium over Stock Price of Convertible Debt																												25.00%
Debt Instrument, Convertible Number of Equity Instruments, Ratio																				19.2944			19.2944					18.263
Interest Expense Debt Amortization															1,600,000	4,500,000	10,900,000	13,500,000
Interest Expense, Debt																				1,200,000		3,600,000	8,400,000		10,800,000
Debt Instruments, Interest Rate Effective Percentage																				5.75%		5.78%	5.73%		5.79%
Debt Instrument, Unamortized Discount							1,000,000																				10,800,000
Business Acquisition, Cost of Acquired Entity, Liabilities Incurred																																																								3,400,000,000	2,700,000,000	585,000,000	500,000,000							500,000,000
Stock Available, Shares, Upon Conversion of Convertible Securities																																																								12,894,044	12,894,044
Repayments of Convertible Debt																																																															614,700,000	466,000,000
Long-term Debt - Portion of Principal Repayment																																																															600,300,000	455,100,000
Derivative Liabilities																																																																										12,100,000
Discounts to Long-term Debt																																																														1,300,000
Commercial Paper, Maximum Borrowing Capacity	950,000,000
Line of Credit Facility, Maximum Borrowing Capacity										400,000,000				550,000,000
Line of Credit Facility, Additional Borrowing Capacity										$ 100,000,000

[1] Our $575 million convertible notes matured and were repaid on July 30, 2013, for their face value of $575 million. The required premium payment of $2.6 million, which was based on our weighted-average Class B common stock price exceeding the then-applicable conversion price on any of the 25 trading days following the maturity date, was paid in September 2013. This premium was hedged by call options that mitigated our exposure to increases in our stock price and resulted in proceeds of $2.6 million from these call options in September 2013, which fully offset the premium payment. Separately, the warrants entered into concurrent with these call options, pursuant to which we may be required to issue Class B common stock to the counterparty when our stock price reaches $66.13 per share, remain outstanding and will expire beginning December 2013 through February 2014. The original conversion price for each $1,000 aggregate principal amount of notes was $54.76 per share of our Class B common stock, which represented a 25% premium above the stock price on the day of issuance of the notes and corresponded to the initial conversion ratio of 18.263 shares per each $1,000 aggregate principal amount of notes. The conversion ratio and conversion price were subject to adjustments for certain events and provisions, as defined in the indenture, including adjustments reflected for exceeding defined thresholds related to our dividend payments. At the maturity date our conversion price and ratio were $51.8284 and 19.2944 shares, respectively. During the third quarters of 2013 and 2012, we incurred additional non-cash interest expense of $1.6 million and $4.5 million, respectively. For the first three quarters of 2013 and 2012, the amounts were $10.9 million and $13.5 million, respectively. We also incurred interest expense related to the 2.5% convertible coupon rate of $1.2 million and $3.6 million during the third quarters of 2013 and 2012, respectively. For the first three quarters of 2013 and 2012, the interest expenses incurred were $8.4 million and $10.8 million, respectively. The combination of non-cash and cash interest resulted in an effective interest rate of 5.75% and 5.78% for the third quarters of 2013, through settlement, and 2012, respectively. The effective interest rates for the first three quarters of 2013, through settlement, and 2012 were 5.73% and 5.79%, respectively. As of September 28, 2013, there was no unamortized debt discount outstanding as we recorded the remaining discount of $1.6 million upon maturity in the third quarter of 2013. As of December 29, 2012, $10.8 million of the unamortized debt discount related to our $575 million convertible debt.

[2] On June 15, 2012, we issued a €500 million Zero Coupon Senior Unsecured Convertible Note due December 31, 2013 (the ''Convertible Note'') to the Seller in conjunction with the closing of the Acquisition. The Seller had the ability to exercise a put right with respect to the Convertible Note as of March 14, 2013, (the “First Redemption Date”) and ending on December 19, 2013, for the greater of the principal amount of the Convertible Note or the aggregate cash value of 12,894,044 shares of our Class B Common Stock, as adjusted for certain corporate events. In accordance with these terms, on August 13, 2013, the Seller exercised the conversion feature for an agreed upon value upon exercise of €510.9 million, consisting of €500 million in principal and €10.9 million for the conversion feature. At issuance, the total value of the Convertible Note was €511.1 million, consisting of the principal (€500 million), discount (€1.0 million), and conversion feature (€12.1 million), initially recorded as a component of the purchase price associated with the Acquisition.Separate from the Seller's notice to put, we have made claims with regard to the representations and warranties provided to us upon close of the Acquisition. As a result, we have withheld €44.9 million ($60.8 million as of September 28, 2013) from the €500 million in principal related to these outstanding claims. The remaining balance continues to be classified as current portion of long-term debt pending the resolution of these claims. Therefore, on September 3, 2013, we paid the seller in cash a total of €466.0 million ($614.7 million) consisting of €455.1 million ($600.3 million) in principal and €10.9 million ($14.4 million) for the conversion feature. The Convertible Note's embedded conversion feature was determined to meet the definition of a derivative required to be bifurcated and separately accounted for at fair value with changes in fair value recorded in earnings. During the third quarter and first three quarters of 2013, we recognized a net gain of $20.3 million and a loss of $6.5 million, respectively, on the conversion feature primarily related to the change from the previously recorded fair value to the value upon exercise. The Convertible Note was issued at a discount of $1.3 million, which has been recognized as interest expense over the period from issuance to the First Redemption Date. The non-cash interest, excluding the change in fair value of the convertible feature, resulted in an immaterial impact to our effective interest rate for the third quarter and first three quarters of 2013. See Note 14, "Derivative Instruments and Hedging Activities" for further discussion.

[3] During the third quarter and first three quarters of 2013, we made principal repayments of $71.8 million (€53.7 million) and $123.8 million (€93.7 million), respectively, on the remaining balance of our €120 million term loan. As a result, the term loan, which was designated as a net investment hedge, was fully repaid in the third quarter of 2013. See Note 14, "Derivative Instruments and Hedging Activities" for further discussion.

[4] In the first quarter of 2013, a $950 million commercial paper program was approved and implemented. The commercial paper program is supported by our $550 million and $400 million revolving credit facilities. To fund the repayment of our €500 million Zero Coupon Senior Unsecured Convertible Note, we issued short-term commercial paper during the third quarter of 2013. As of September 28, 2013, the outstanding borrowings under the commercial paper program were $391.1 million.In the third quarter of 2012, we entered into a 1-year, €150 million revolving credit agreement, on an uncommitted basis, to support our operations in Central Europe within our Europe segment. In the third quarter of 2013, this revolving credit facility was renewed and restructured and will continue to provide €150 million on an uncommitted basis through September 2014. As of September 28, 2013, the outstanding borrowings under this revolving credit facility were $162.3 million. There were no outstanding borrowings under this revolving credit facility as of December 29, 2012.In the second quarter of 2012, we entered into a 4-year, $550 million revolving credit agreement. This credit agreement contains customary events of default and specified representations and warranties and covenants, including, among other things, covenants that limit our subsidiaries' ability to incur certain additional priority indebtedness, create or permit liens on assets, or engage in mergers or consolidations. As of September 28, 2013, and December 29, 2012, there were no outstanding borrowings under this revolving credit facility. In the second quarter of 2011, we entered into an agreement for a 4-year, $400 million revolving multicurrency credit facility, which provides a $100 million sub-facility available for the issuance of letters of credit. As of September 28, 2013 and December 29, 2012, there were no outstanding borrowings under this revolving credit facility. The remaining outstanding balances as of September 28, 2013, and December 29, 2012, relate to other short-term borrowings.