Acquisition of StarBev - Pro Forma Results (Details) In Millions, except Per Share data, unless otherwise specified	3 Months Ended		9 Months Ended		0 Months Ended	3 Months Ended		9 Months Ended			3 Months Ended				9 Months Ended				3 Months Ended		9 Months Ended		6 Months Ended		0 Months Ended				6 Months Ended	0 Months Ended		6 Months Ended
	Sep. 28, 2013 USD ($)	Sep. 29, 2012 USD ($)	Sep. 28, 2013 USD ($)	Sep. 29, 2012 USD ($)	Jun. 15, 2012 Molson Coors Central Europe (MCCE) USD ($)	Sep. 28, 2013 Molson Coors Central Europe (MCCE) USD ($)	Sep. 29, 2012 Molson Coors Central Europe (MCCE) USD ($)	Sep. 28, 2013 Molson Coors Central Europe (MCCE) USD ($)	Sep. 29, 2012 Molson Coors Central Europe (MCCE) USD ($)	Jun. 15, 2012 Molson Coors Central Europe (MCCE) EUR (€)	Sep. 28, 2013 Europe [Member] USD ($)		Sep. 29, 2012 Europe [Member] USD ($)		Sep. 28, 2013 Europe [Member] USD ($)		Sep. 29, 2012 Europe [Member] USD ($)		Sep. 28, 2013 Europe [Member] Molson Coors Central Europe (MCCE) USD ($)	Sep. 29, 2012 Europe [Member] Molson Coors Central Europe (MCCE) USD ($)	Sep. 28, 2013 Europe [Member] Molson Coors Central Europe (MCCE) USD ($)	Sep. 29, 2012 Europe [Member] Molson Coors Central Europe (MCCE) USD ($)	Jun. 30, 2012 Fair Value Adjustment to Acquisition Date Inventory [Member] USD ($)	Jun. 30, 2012 Euro Currency Purchase Loss [Member] USD ($)	Jun. 15, 2012 Convertible, Unsecured Debt [Member] Molson Coors Central Europe (MCCE) USD ($)	Jun. 15, 2012 Convertible, Unsecured Debt [Member] Molson Coors Central Europe (MCCE) EUR (€)	Jun. 15, 2012 Senior Notes [Member] Molson Coors Central Europe (MCCE) USD ($)	Jun. 15, 2012 Senior Notes [Member] Molson Coors Central Europe (MCCE) EUR (€)	Jun. 30, 2012 Senior Notes [Member] Bridge Facility Fees [Member] USD ($)	Jun. 29, 2012 Subordinated Deferred Payment Obligation, Including Interest and Other Costs [Member] Molson Coors Central Europe (MCCE) USD ($)	Jun. 15, 2012 Zero Coupon Senior Unsecured Note [Member] Convertible, Unsecured Debt [Member] Molson Coors Central Europe (MCCE) EUR (€)	Jun. 30, 2012 Interest Expense [Member] Not Designated as Hedging Instrument [Member] Interest Rate Contract [Member] Treasury Lock Loss [Member] USD ($)
Business Acquisition [Line Items]
Noncash or Part Noncash Acquisition, Debt Assumed									$ 645.9																$ 645.9	€ 511.1
Business acquisition, cost of acquired entity, liabilities incurred					3,400.0					2,700.0																	585.0	500.0			500.0
Cash Acquired from Acquisition					143.6
Interest Expense, Debt																														1.4
Business acquisition-related costs						4.4	5.1	8.3	36.5
Net sales	1,171.2	1,195.5	3,177.7	2,886.3		272.2	270.9	676.1	328.2		607.9		577.7		1,600.5		1,224.6		264.8	264.2	655.2	321.5
Income (loss) from continuing operations before income taxes	155.4	243.2	509.2	463.6		(88.6)	78.0	(49.7)	90.4		(69.5)	[1]	82.9	[1]	8.4	[1]	112.9	[1]	(92.1)	75.2	(59.4)	87.6
Business Acquisition, Pro Forma Information
Net sales, pro forma									3,226.8
Inome (loss) from continuing operations before income taxes, pro forma									592.3
Net income (loss) attributable to MCBC, pro forma									499.0
Net income per common share attributable to MCBC, Basic, pro forma									$ 2.76
Net income per common share attributable to MCBC, Diluted, pro forma									$ 2.75
Business Acquisition, Pro Forma Adjustments																							8.6	57.9					13.0
Derivative Instruments Not Designated as Hedging Instruments, Gain (Loss), Net																																$ (39.2)

[1] The third quarter and first three quarters of 2013 include an impairment charge to indefinite-lived intangible assets recorded in the third quarter of 2013, which is the primary driver of the decrease from the comparable periods in 2012. See Note 11, "Goodwill and Intangible Assets" for further discussion.