Commitments and Contingencies - Summary of Activity for ARO Liabilities (Detail) $ in Thousands |
9 Months Ended |
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Sep. 30, 2018
USD ($)
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| Commitments And Contingencies Disclosure [Abstract] | |
| Balance as of December 31, 2017 | $ 580 |
| Liabilities incurred during the period | 88 |
| Accretion expense | 32 |
| Balance as of September 30, 2018 | $ 700 |
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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. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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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. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount of asset retirement obligations incurred during the period. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- References No definition available.
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