CLOSURE AND POST-CLOSURE LIABILITIES (Details) (USD $) In Thousands, unless otherwise specified	9 Months Ended
Sep. 30, 2011
Changes to post-closure liabilities
Balance at the beginning of the period	$ 38,679
Liabilities assumed in acquisitions	196
New asset retirement obligations	1,749
Accretion	2,496
Changes in estimates recorded to statement of income	(951)
Other changes in estimates recorded to balance sheet	(6,029)
Settlement of obligations	(3,452)
Currency translation and other	(182)
Balance at the end of the period	32,506
Credit-adjusted risk-free rate (as a percent)	8.79%
Inflation rate (as a percent)	1.01%
Landfill Retirement Liability
Changes to post-closure liabilities
Balance at the beginning of the period	29,756
Liabilities assumed in acquisitions
New asset retirement obligations	1,749
Accretion	1,654
Changes in estimates recorded to statement of income	(936)
Other changes in estimates recorded to balance sheet	(6,150)
Settlement of obligations	(3,011)
Currency translation and other	(141)
Balance at the end of the period	22,921
Non-Landfill Retirement Liability
Changes to post-closure liabilities
Balance at the beginning of the period	8,923
Liabilities assumed in acquisitions	196
New asset retirement obligations
Accretion	842
Changes in estimates recorded to statement of income	(15)
Other changes in estimates recorded to balance sheet	121
Settlement of obligations	(441)
Currency translation and other	(41)
Balance at the end of the period	$ 9,585

The amount of change in the asset retirement obligation, during the current period, for changes in estimates recorded in the statement of income.

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The total amount of the increase or decrease in the amount of asset retirement obligations for the period that is associated with foreign currency translation (to the extent that the entity accounts for the foreign currency effects as a separate component of the change in the liability) and other asset retirement obligations.

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Represents the amount of change in the asset retirement obligation, during the current period for other changes in estimates recorded in the balance sheet.

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Asset Retirement Obligations, Liabilities Assumed in Acquisitions

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The rate applied to the undiscounted amount of new asset retirement obligations that are expected to arrive at the present value and that are recorded as of the balance sheet date.

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The inflation rate that is applied to the amount of new asset retirement obligations, which are expected to arrive at the present value and that are recorded as of the balance sheet date.

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- Definition

The carrying amount of a liability for an asset retirement obligation. An asset retirement obligation is a legal obligation associated with the disposal or retirement of a tangible long-lived asset that results from the acquisition, construction or development, or the normal operations of a long-lived asset, except for certain obligations of lessees.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 143

-Paragraph 3, 10, 22

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-Name Accounting Standards Codification

-Glossary Asset Retirement Obligation

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Amount of accretion expense recognized during the period that is associated with an asset retirement obligation. Accretion expense measures and incorporates changes due to the passage of time into the carrying amount of the liability.

+ References

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

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

-Publisher FASB

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Amount of asset retirement obligations incurred during the period.

+ References

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 143

-Paragraph 22

-Subparagraph c(1)

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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Amount of asset retirement obligations settled, or otherwise disposed of, during the period. This may include asset retirement obligations transferred to third parties associated with the sale of a long-lived asset.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 143

-Paragraph 22

-Subparagraph c(2)

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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