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Asset Retirement Obligations (Tables)

12 Months Ended

Dec. 31, 2020

Asset Retirement Obligation Disclosure [Abstract]

Schedule of changes in asset retirement obligations

The reconciliation of the changes in our AROs is presented below:

			Year ended December 31,
			2020						2019
Beginning balance, ARO liability			$	18.9					$	18.2
Additional ARO liability incurred			2.3						2.9
ARO liabilities settled			(2.2)						(3.5)
Accretion expense			1.3						1.3
Revisions in estimated cash flows			(0.5)						—
Ending balance, ARO liability			$	19.8					$	18.9

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- References

No definition available.

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- Definition

Tabular disclosure of the changes in carrying amount of a liability for asset retirement obligations, for changes such as new obligations, changes in estimates of existing obligations, spending on existing obligations, property dispositions, and foreign currency translation.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 410
-SubTopic 30
-Section 50
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=6393242&loc=d3e13201-110859

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