Acquisition and Investments Fair Value of Consideration Transferred (Details) - USD ($) $ in Millions		3 Months Ended	12 Months Ended
	Oct. 11, 2016	Dec. 31, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Oct. 10, 2016
Business Acquisition [Line Items]
Business Combination, Step Acquisition, Equity Interest in Acquiree, Remeasurement Loss			$ 0.0	$ 82.0	$ 0.0
Business Combination, Step Acquisition, Equity Interest in Acquiree, Remeasurement Gain			0.0	2,965.0	0.0
Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI on Historical Shares, Net of Tax			0.0	(258.2)	0.0
Deferred Income Tax Expense (Benefit)			82.7	927.9	(91.6)
Income tax benefit (expense)			(53.2)	$ 1,055.2	$ 61.5
Millercoors [Member]
Business Acquisition [Line Items]
MCBC economic Interest (as a percent)	42.00%
Business Combination, Consideration Transferred	$ 12,000.0
Business Combination, Consideration Transferred, Equity Interests Issued and Issuable	46.4
Business Combination, Consideration Transferred, Liabilities Eliminated	(8.0)
Business Combination, Consideration Transferred	12,038.4
Business Combination, Step Acquisition, Equity Interest in Acquiree, Fair Value	6,090.0
Business Combination, Consideration Transferred, Including Equity Interest in Acquiree Held Prior to Combination	18,128.4
Deferred Income Tax Expense (Benefit)		$ 1,100.0
Income tax benefit (expense)	$ 200.1
Millercoors [Member]
Business Acquisition [Line Items]
MCBC economic Interest (as a percent)	100.00%	42.00%		42.00%	42.00%	42.00%
Investment in MillerCoors						$ 2,666.7
Reclassification out of Accumulated Other Comprehensive Income | Accumulated Net Gain (Loss) from Reclassification of Historical Shares Attributable to Parent [Member] | Millercoors [Member]
Business Acquisition [Line Items]
Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI on Historical Shares, Net of Tax		$ 458.3
Reclassification out of Accumulated Other Comprehensive Income | Accumulated Net Gain (Loss) from Reclassification of Historical Shares Attributable to Parent [Member] | Millercoors [Member]
Business Acquisition [Line Items]
Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI on Historical Shares, Net of Tax			0.0	$ (458.3)	$ 0.0
Income tax benefit (expense)			$ 0.0	$ 200.1	$ 0.0