CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (LOSS) (USD $) In Millions, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Net income (loss) including noncontrolling interests	$ 82.6us-gaap_ProfitLoss	$ 162.9us-gaap_ProfitLoss
Other comprehensive income (loss), net of tax:
Foreign currency translation adjustments	(664.3)	(182.0)
Unrealized gain (loss) on derivative instruments	18.9	14.5
Reclassification of derivative (gain) loss to income	(1.4)	(3.2)
Pension and other postretirement benefit adjustments	(1.8)	0
Amortization of net prior service (benefit) cost and net actuarial (gain) loss to income	9.0	7.6
Ownership share of unconsolidated subsidiaries' other comprehensive income (loss)	2.2	1.6
Total other comprehensive income (loss), net of tax	(637.4)	(161.5)
Comprehensive income (loss)	(554.8)	1.4
Comprehensive (income) loss attributable to noncontrolling interests	(1.5)	0.5
Comprehensive income (loss) attributable to Molson Coors Brewing Company	$ (556.3)us-gaap_ComprehensiveIncomeNetOfTax	$ 1.9us-gaap_ComprehensiveIncomeNetOfTax

Other Comprehensive Income (Loss), Amortization of Net Prior Service Costs and Net Actuarial Losses

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This element represents the Company's share in the Other Comprehensive Income (Loss), Net of Tax, for the period, pertaining to its equity method investments.

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Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

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Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income (loss) and other comprehensive income (loss), attributable to noncontrolling interests. Excludes changes in equity resulting from investments by owners and distributions to owners.

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Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income. Excludes changes in equity resulting from investments by owners and distributions to owners.

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Amount after tax and reclassification adjustments of gain (loss) on foreign currency translation adjustments, foreign currency transactions designated and effective as economic hedges of a net investment in a foreign entity and intra-entity foreign currency transactions that are of a long-term-investment nature.

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Amount after tax and reclassification adjustments of other comprehensive income (loss).

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Amount after tax and reclassification adjustments, of (increase) decrease in accumulated other comprehensive (income) loss related to pension and other postretirement defined benefit plans.

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Amount after tax of reclassification adjustment from accumulated other comprehensive income of accumulated gain (loss) realized from derivative instruments designated and qualifying as the effective portion of cash flow hedges and an entity's share of an equity investee's deferred hedging gain (loss).

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Amount after tax of increase (decrease) in accumulated gain (loss) from derivative instruments designated and qualifying as the effective portion of cash flow hedges and an entity's share of an equity investee's increase (decrease) in deferred hedging gain (loss).

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The consolidated profit or loss for the period, net of income taxes, including the portion attributable to the noncontrolling interest.

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