CLOSURE AND POST-CLOSURE LIABILITIES - Changes in Post-Closure Liabilities (Details) $ in Thousands	9 Months Ended
Sep. 30, 2021 USD ($)
Changes to post-closure liabilities
Balance at January 1, 2021	$ 87,926
Liabilities assumed in acquisitions	451
New asset retirement obligations	1,979
Accretion	5,344
Changes in estimates recorded to consolidated statement of operations	326
Changes in estimates recorded to consolidated balance sheet	1,894
Expenditures	(4,881)
Currency translation and other	(11)
Balance at September 30, 2021	93,028
Landfill Retirement Liability
Changes to post-closure liabilities
Balance at January 1, 2021	48,412
Liabilities assumed in acquisitions	0
New asset retirement obligations	1,979
Accretion	2,600
Changes in estimates recorded to consolidated statement of operations	35
Changes in estimates recorded to consolidated balance sheet	668
Expenditures	(4,420)
Currency translation and other	0
Balance at September 30, 2021	49,274
Non-Landfill Retirement Liability
Changes to post-closure liabilities
Balance at January 1, 2021	39,514
Liabilities assumed in acquisitions	451
New asset retirement obligations	0
Accretion	2,744
Changes in estimates recorded to consolidated statement of operations	291
Changes in estimates recorded to consolidated balance sheet	1,226
Expenditures	(461)
Currency translation and other	(11)
Balance at September 30, 2021	$ 43,754

Asset Retirement Obligation Changes Recorded in Balance Sheet

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- Definition

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

+ References

No definition available.

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- Definition

Asset Retirement Obligation Liabilities Assumed in Acquisition

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No definition available.

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- Definition

Asset Retirement Obligation, Payments

+ References

No definition available.

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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

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- Definition

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://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 410
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (c)(3)
-URI http://asc.fasb.org/extlink&oid=6392692&loc=d3e7535-110849

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 410
-SubTopic 20
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6392676&loc=d3e7480-110848

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- Definition

Amount of foreign currency translation gain (loss) which decreases (increases) asset retirement obligations.

+ References

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- Definition

Amount of asset retirement obligations incurred during the period.

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- Definition

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

+ References

No definition available.

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