CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (Unaudited) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Statement of Comprehensive Income [Abstract]
Consolidated net income	$ 1,338us-gaap_ProfitLoss	$ 130us-gaap_ProfitLoss	$ 860us-gaap_ProfitLoss
Derivative instruments, net	1	12	(12)
Available-for-sale securities, net	4	2	2
Foreign currency translation adjustments	(124)	(68)	33
Post-retirement benefit obligation, net	(12)	15	(2)
Other comprehensive income (loss), net of taxes	(131)	(39)	21
Comprehensive income	1,207	91	881
Less: Comprehensive income attributable to noncontrolling interests	40	32	43
Comprehensive income attributable to Waste Management, Inc.	$ 1,167us-gaap_ComprehensiveIncomeNetOfTax	$ 59us-gaap_ComprehensiveIncomeNetOfTax	$ 838us-gaap_ComprehensiveIncomeNetOfTax

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 and other comprehensive income, attributable to noncontrolling interests. Excludes changes in equity resulting from investments by owners and distributions to owners.

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Amount after tax and reclassification adjustments, of appreciation (loss) in value of unsold available-for-sale securities. Excludes amounts related to other than temporary impairment (OTTI) loss.

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Amount after tax and reclassification adjustments, 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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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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The consolidated profit or loss for the period, net of income taxes, including the portion attributable to the noncontrolling interest.

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