CLOSURE AND POST-CLOSURE LIABILITIES (Details) $ in Thousands	6 Months Ended
Jun. 30, 2020 USD ($) facility
Changes to post-closure liabilities
Balance at January 1, 2020	$ 75,651
Liabilities assumed in acquisitions	265
New asset retirement obligations	1,080
Accretion	3,176
Changes in estimates recorded to statement of operations	4,467
Changes in estimates recorded to balance sheet	76
Expenditures	(1,745)
Currency translation and other	(329)
Balance at June 30, 2020	$ 82,641
Number of active landfill facilities \| facility	10
Credit-adjusted risk-free rate	5.60%
Landfill Retirement Liability
Changes to post-closure liabilities
Balance at January 1, 2020	$ 39,401
Liabilities assumed in acquisitions	0
New asset retirement obligations	1,080
Accretion	1,521
Changes in estimates recorded to statement of operations	4,503
Changes in estimates recorded to balance sheet	129
Expenditures	(1,254)
Currency translation and other	(249)
Balance at June 30, 2020	45,131
Non-Landfill Retirement Liability
Changes to post-closure liabilities
Balance at January 1, 2020	36,250
Liabilities assumed in acquisitions	265
New asset retirement obligations	0
Accretion	1,655
Changes in estimates recorded to statement of operations	(36)
Changes in estimates recorded to balance sheet	(53)
Expenditures	(491)
Currency translation and other	(80)
Balance at June 30, 2020	$ 37,510

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 Obligations Discount Rate

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- Definition

Number Of Active Landfill Facilities

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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.

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

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Amount of asset retirement obligations incurred during the period.

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- Definition

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.

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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.

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