Asset Retirement Obligation - Summary of Asset Retirement Obligation (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017
Asset Retirement Obligation Disclosure [Abstract]
Balance, beginning of period	$ 5,731	$ 4,789
Liabilities settled	(521)	(97)
Accretion expense	993	1,039
Balance, end of period	6,203	5,731
Less: Included in liabilities held for sale
Less: Current portion	(708)	(1,078)
Non-current Portion	$ 5,495	$ 4,653

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

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 410
-SubTopic 20
-Section 50
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- Definition

Current portion of 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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- References

No definition available.

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- Definition

Amount of asset retirement obligations incurred during the period.

+ References

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- Definition

Noncurrent portion of 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 classified as liabilities attributable to disposal group held for sale or disposed of.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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-Publisher FASB
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