Quarterly Financial Information (Unaudited) Quarterly Financial Information (Details) (USD $) In Millions, except Per Share data, unless otherwise specified	3 Months Ended								12 Months Ended
	Dec. 31, 2013	Sep. 28, 2013	Jun. 29, 2013	Mar. 30, 2013	Dec. 29, 2012	Sep. 29, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2013	Dec. 29, 2012	Dec. 31, 2011
Quarterly Financial Information Disclosure [Abstract]
Sales	$ 1,489.7	$ 1,665.4	$ 1,659.7	$ 1,184.8	$ 1,480.2	$ 1,685.8	$ 1,440.9	$ 1,008.1	$ 5,999.6	$ 5,615.0	$ 5,169.9
Excise taxes	(461.3)	(494.2)	(481.7)	(356.3)	(450.0)	(490.3)	(441.5)	(316.7)	(1,793.5)	(1,698.5)	(1,654.2)
Net sales	1,028.4	1,171.2	1,178.0	828.5	1,030.2	1,195.5	999.4	691.4	4,206.1	3,916.5	3,515.7
Cost of goods sold	(644.4)	(670.0)	(684.1)	(547.1)	(646.6)	(687.0)	(580.1)	(438.8)	(2,545.6)	(2,352.5)	(2,049.1)
Gross profit	384.0	501.2	493.9	281.4	383.6	508.5	419.3	252.6	1,660.5	1,564.0	1,466.6
Amounts attributable to MCBC
Net income (loss) from continuing operations	131.2	120.9	276.7	36.5	60.1	197.7	104.3	79.4	565.3	441.5	674.0
Income (loss) from discontinued operations, net of tax	0.3	0.9	1.7	(0.9)	(0.1)	0.7	0.8	0.1	2.0	1.5	2.3
Net income (loss) attributable to Molson Coors Brewing Company	$ 131.5	$ 121.8	$ 278.4	$ 35.6	$ 60.0	$ 198.4	$ 105.1	$ 79.5	$ 567.3	$ 443.0	$ 676.3
Basic net income (loss) attributable to Molson Coors Brewing Company per share(1):
From continuing operations (in dollars per share)	$ 0.72	$ 0.65	$ 1.51	$ 0.20	$ 0.33	$ 1.09	$ 0.58	$ 0.44	$ 3.09	$ 2.44	$ 3.65
From discontinued operations (in dollars per share)	$ 0.00	$ 0.01	$ 0.01	$ 0.00	$ 0.00	$ 0.00	$ 0.00	$ 0.00	$ 0.01	$ 0.01	$ 0.01
Basic net income per share (in dollars per share)	$ 0.72	$ 0.66	$ 1.52	$ 0.20	$ 0.33	$ 1.09	$ 0.58	$ 0.44	$ 3.10	$ 2.45	$ 3.66
Diluted net income (loss) attributable to Molson Coors Brewing Company per share(1):
From continuing operations (in dollars per share)	$ 0.71	$ 0.65	$ 1.50	$ 0.20	$ 0.33	$ 1.09	$ 0.57	$ 0.44	$ 3.07	$ 2.43	$ 3.62
From discontinued operations (in dollars per share)	$ 0.00	$ 0.01	$ 0.01	$ 0.00	$ 0.00	$ 0.00	$ 0.00	$ 0.00	$ 0.01	$ 0.01	$ 0.01
Diluted net income per share (in dollars per share)	$ 0.71	$ 0.66	$ 1.51	$ 0.20	$ 0.33	$ 1.09	$ 0.57	$ 0.44	$ 3.08	$ 2.44	$ 3.63