Share-Based Payments Narrative (Details) shares in Millions	12 Months Ended
Dec. 31, 2017 Share-based_Compensation_Plans $ / shares shares	Dec. 31, 2016 $ / shares shares	Dec. 31, 2015 $ / shares shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of share-based compensation plans \| Share-based_Compensation_Plans	1
RSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period	3 years
Awards granted (in shares) \| shares	0.3	0.2	0.2
Equity instruments other than options, nonvested, weighted average grant date fair value	$ 92.02	$ 92.95	$ 71.45
RSUs \| Millercoors [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Awards granted (in shares) \| shares		0.4
Granted, weighted-average grant date fair value (in dollars per unit)		$ 107.91
DSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Equity instruments other than options, nonvested, weighted average grant date fair value	$ 86.06	$ 100.60	$ 79.34
Performance shares (PSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Awards granted (in shares) \| shares	0.2	0.1	0.1
Equity instruments other than options, nonvested, weighted average grant date fair value	$ 89.57	$ 81.67
Granted, weighted-average grant date fair value (in dollars per unit)	$ 97.13	$ 90.49	$ 74.42
Performance shares (PSUs) \| Millercoors [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Awards granted (in shares) \| shares		0.1
Granted, weighted-average grant date fair value (in dollars per unit)		$ 106.17
Stock options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Annual Vesting Percentage	33.33%
Award vesting period	3 years
Awards granted (in shares) \| shares	0.2	0.1	0.1
Equity instruments other than options, nonvested, weighted average grant date fair value		$ 16.65	$ 13.98
Terms of SBC award	10 years
Stock options \| Millercoors [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Awards granted (in shares) \| shares		0.5
Equity instruments other than options, nonvested, weighted average grant date fair value		$ 42.21

Number of Share-based Compensation Plans

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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Options, Annual Vesting Percentage

+ References

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- Definition

Share Based Compensation Arrangement By Share Based Payment Award Term Of Award

+ References

No definition available.

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- Definition

Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)(iii)(1)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)(iii)(1)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

The weighted average fair value of nonvested awards on equity-based plans excluding option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, revenue or profit achievement stock award plan) for which the employer is contingently obligated to issue equity instruments or transfer assets to an employee who has not yet satisfied service or performance criteria necessary to gain title to proceeds from the sale of the award or underlying shares or units.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)(i)-(ii)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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