Supplemental Guarantor Information Income statement (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS
Sales Revenue, Goods, Gross	$ 2,913.8	$ 950.8
Excise taxes	(465.1)	(293.6)
Net sales	2,448.7	657.2
Cost of goods sold	(1,372.9)	(414.0)
Gross profit	1,075.8	243.2
Marketing, general and administrative expenses	(702.8)	(250.9)
Special items, net	(3.8)	108.6
Equity income in MillerCoors	0.0	142.4
Operating income (loss)	369.2	243.3
Interest income (expense), net	(96.6)	(47.3)
Other income (expense), net	0.4	(15.3)
Income (loss) from continuing operations before income taxes	273.0	180.7
Income tax benefit (expense)	(64.6)	(16.7)
Net Income (loss) from continuing operations	208.4	164.0
Income (loss) from discontinued operations, net of tax	(0.6)	(0.5)
Net income (loss) including noncontrolling interests	207.8	163.5
Net (income) loss attributable to noncontrolling interests	(6.5)	(0.8)
Net income (loss) attributable to Molson Coors Brewing Company	201.3	162.7
Comprehensive income (loss) attributable to Molson Coors Brewing Company		419.7
Parent Company [Member]
CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS
Sales Revenue, Goods, Gross	7.0	6.6
Excise taxes	0.0	0.0
Net sales	7.0	6.6
Cost of goods sold	0.0	0.0
Gross profit	7.0	6.6
Marketing, general and administrative expenses	(67.7)	(47.0)
Special items, net	(0.5)	0.0
Equity income (loss) in subsidiaries	338.8	215.8
Equity income in MillerCoors		0.0
Operating income (loss)	277.6	175.4
Interest income (expense), net	(81.1)	(39.9)
Other income (expense), net	(8.2)	(18.3)
Income (loss) from continuing operations before income taxes	188.3	117.2
Income tax benefit (expense)	13.0	45.5
Net Income (loss) from continuing operations	201.3	162.7
Income (loss) from discontinued operations, net of tax	0.0	0.0
Net income (loss) including noncontrolling interests	201.3	162.7
Net (income) loss attributable to noncontrolling interests	0.0	0.0
Net income (loss) attributable to Molson Coors Brewing Company	201.3	162.7
Comprehensive income (loss) attributable to Molson Coors Brewing Company		419.7
Subsidiary Guarantors [Member]
CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS
Sales Revenue, Goods, Gross	2,376.6	375.9
Excise taxes	(325.7)	(84.0)
Net sales	2,050.9	291.9
Cost of goods sold	(1,143.0)	(163.7)
Gross profit	907.9	128.2
Marketing, general and administrative expenses	(497.6)	(79.8)
Special items, net	(0.7)	109.3
Equity income (loss) in subsidiaries	(78.1)	(113.4)
Equity income in MillerCoors		142.4
Operating income (loss)	331.5	186.7
Interest income (expense), net	58.9	69.2
Other income (expense), net	16.7	4.6
Income (loss) from continuing operations before income taxes	407.1	260.5
Income tax benefit (expense)	(68.1)	(85.4)
Net Income (loss) from continuing operations	339.0	175.1
Income (loss) from discontinued operations, net of tax	0.0	0.0
Net income (loss) including noncontrolling interests	339.0	175.1
Net (income) loss attributable to noncontrolling interests	0.0	0.0
Net income (loss) attributable to Molson Coors Brewing Company	339.0	175.1
Comprehensive income (loss) attributable to Molson Coors Brewing Company	412.9	408.8
Subsidiary Non Guarantors [Member]
CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS
Sales Revenue, Goods, Gross	650.0	595.3
Excise taxes	(139.4)	(209.6)
Net sales	510.6	385.7
Cost of goods sold	(339.4)	(270.4)
Gross profit	171.2	115.3
Marketing, general and administrative expenses	(147.8)	(131.0)
Special items, net	(2.6)	(0.7)
Equity income (loss) in subsidiaries	19.0	149.3
Equity income in MillerCoors		0.0
Operating income (loss)	39.8	132.9
Interest income (expense), net	(74.4)	(76.6)
Other income (expense), net	(8.1)	(1.6)
Income (loss) from continuing operations before income taxes	(42.7)	54.7
Income tax benefit (expense)	(9.5)	23.2
Net Income (loss) from continuing operations	(52.2)	77.9
Income (loss) from discontinued operations, net of tax	(0.6)	(0.5)
Net income (loss) including noncontrolling interests	(52.8)	77.4
Net (income) loss attributable to noncontrolling interests	(6.5)	(0.8)
Net income (loss) attributable to Molson Coors Brewing Company	(59.3)	76.6
Comprehensive income (loss) attributable to Molson Coors Brewing Company	(13.8)	99.4
Consolidated [Member]
CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS
Sales Revenue, Goods, Gross	2,913.8	950.8
Excise taxes	(465.1)	(293.6)
Net sales	2,448.7	657.2
Cost of goods sold	(1,372.9)	(414.0)
Gross profit	1,075.8	243.2
Marketing, general and administrative expenses	(702.8)	(250.9)
Special items, net	(3.8)	108.6
Equity income (loss) in subsidiaries	0.0	0.0
Equity income in MillerCoors		142.4
Operating income (loss)	369.2	243.3
Interest income (expense), net	(96.6)	(47.3)
Other income (expense), net	0.4	(15.3)
Income (loss) from continuing operations before income taxes	273.0	180.7
Income tax benefit (expense)	(64.6)	(16.7)
Net Income (loss) from continuing operations	208.4	164.0
Income (loss) from discontinued operations, net of tax	(0.6)	(0.5)
Net income (loss) including noncontrolling interests	207.8	163.5
Net (income) loss attributable to noncontrolling interests	(6.5)	(0.8)
Net income (loss) attributable to Molson Coors Brewing Company	201.3	162.7
Comprehensive income (loss) attributable to Molson Coors Brewing Company	276.6	419.7
Consolidation, Eliminations [Member]
CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS
Sales Revenue, Goods, Gross	(119.8)	(27.0)
Excise taxes	0.0	0.0
Net sales	(119.8)	(27.0)
Cost of goods sold	109.5	20.1
Gross profit	(10.3)	(6.9)
Marketing, general and administrative expenses	10.3	6.9
Special items, net	0.0	0.0
Equity income (loss) in subsidiaries	(279.7)	(251.7)
Equity income in MillerCoors		0.0
Operating income (loss)	(279.7)	(251.7)
Interest income (expense), net	0.0	0.0
Other income (expense), net	0.0	0.0
Income (loss) from continuing operations before income taxes	(279.7)	(251.7)
Income tax benefit (expense)	0.0	0.0
Net Income (loss) from continuing operations	(279.7)	(251.7)
Income (loss) from discontinued operations, net of tax	0.0	0.0
Net income (loss) including noncontrolling interests	(279.7)	(251.7)
Net (income) loss attributable to noncontrolling interests	0.0	0.0
Net income (loss) attributable to Molson Coors Brewing Company	(279.7)	(251.7)
Comprehensive income (loss) attributable to Molson Coors Brewing Company	$ (399.1)	$ (508.2)