Landfill Accounting (Reconciliation of Final Capping, Closure and Post-Closure Liability Balance) (Details) - USD ($) $ in Thousands	9 Months Ended
Sep. 30, 2020	Sep. 30, 2019
Landfill Accounting [Abstract]
Final capping, closure and post-closure liability at the beginning of the period	$ 291,474
Liabilities incurred	(1,861)
Accretion expense associated with landfill obligations	11,174	$ 10,656
Closure payments	(3,257)
Assumption of closure liabilities from acquisitions	2,135
Foreign currency translation adjustment	(1,178)
Final capping, closure and post-closure liability at the end of the period	$ 298,487

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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Period Type:	instant

- 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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- References

No definition available.

+ Details

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- Definition

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

+ References

+ Details

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- Definition

Amount of asset retirement obligations incurred during the period.

+ References

+ Details

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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.

+ References

+ Details

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- Definition

Asset retirement obligation assumption of closure liabilities from acquisitions.

+ References

No definition available.

+ Details

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