Condensed Consolidating Financial Statements - Condensed Consolidating Statements of Comprehensive Income (Detail) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Condensed Income Statements, Captions [Line Items]
Comprehensive income (loss)	$ 280	$ 223	$ 365	$ 663
Less: Comprehensive income (loss) attributable to noncontrolling interests	2	11	(1)	32
Comprehensive income (loss) attributable to Waste Management, Inc.	278	212	366	631
Eliminations [Member]
Condensed Income Statements, Captions [Line Items]
Comprehensive income (loss)	(759)	(653)	(1,900)	(1,715)
Comprehensive income (loss) attributable to Waste Management, Inc.	(759)	(653)	(1,900)	(1,715)
WM [Member]
Condensed Income Statements, Captions [Line Items]
Comprehensive income (loss)	336	271	487	708
Comprehensive income (loss) attributable to Waste Management, Inc.	336	271	487	708
WM Holdings [Member]
Condensed Income Statements, Captions [Line Items]
Comprehensive income (loss)	378	324	929	867
Comprehensive income (loss) attributable to Waste Management, Inc.	378	324	929	867
Non-Guarantor Subsidiaries [Member]
Condensed Income Statements, Captions [Line Items]
Comprehensive income (loss)	325	281	849	803
Less: Comprehensive income (loss) attributable to noncontrolling interests	2	11	(1)	32
Comprehensive income (loss) attributable to Waste Management, Inc.	$ 323	$ 270	$ 850	$ 771

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.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Other Comprehensive Income

-URI http://asc.fasb.org/extlink&oid=51831270

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Comprehensive Income

-URI http://asc.fasb.org/extlink&oid=51831223

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 220

-SubTopic 10

-Section 45

-Paragraph 5

-URI http://asc.fasb.org/extlink&oid=36458714&loc=d3e557-108580

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Net Income

-URI http://asc.fasb.org/extlink&oid=51831255

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

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-Topic 810

-SubTopic 10

-Section 45

-Paragraph 21

-URI http://asc.fasb.org/extlink&oid=51664549&loc=SL4613674-111683

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

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-URI http://asc.fasb.org/extlink&oid=51664549&loc=SL4569616-111683

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