The total cost of the acquired entity including the cash paid to shareholders of acquired entities, fair value of debt and equity securities issued to shareholders of acquired entities, the fair value of the liabilities assumed, and direct costs of the acquisition.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 141
-Paragraph 51
-Subparagraph d

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Name of the acquired entity.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 141R
-Paragraph 68
-Subparagraph a

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 141
-Paragraph 51
-Subparagraph a

+ Details

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Namespace Prefix:	us-gaap
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- Definition

Total revenue reported by the acquired entity for its previous full fiscal year before the business acquisition.

+ Details

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Data Type:	xbrli:monetaryItemType
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- Definition

This element represents a description of the primary reason for the business combination which may consist of general categories such as top-line growth, synergistic benefits, market share, and diversification and the more detailed factors that might apply.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 141
-Paragraph 51
-Subparagraph b

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 141R
-Paragraph 68
-Subparagraph d

+ Details

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Balance Type:	na
Period Type:	duration

- Definition

Revolving credit facility, total capacity

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Namespace Prefix:	wm
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Subsequent Event.

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Subsequent Event (Details) (USD $)	1 Months Ended	12 Months Ended
Subsequent Event (Details) (USD $)	Jul. 31, 2011	Dec. 31, 2010	Jul. 28, 2011	Jun. 30, 2011
Subsequent Event (Textuals) [Abstract]
Name of acquired entity	Oakleaf Global Holdings
Cost of acquired entity, purchase price			$ 425,000,000
Revolving credit facility, total capacity				2,000,000,000
Revenue reported by acquired entity for last annual period		$ 580,000,000
Reason for business combination	We acquired Oakleaf Global Holdings to advance our growth and transformation strategies. The acquisition is intended to increase our national accounts customer base and enhance our ability to provide comprehensive environmental solutions.