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Asset Retirement Obligations - Additional Information (Detail) - USD ($) | Dec. 31, 2018 | Dec. 31, 2017
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Asset Retirement Obligation Disclosure [Abstract] |  |
Accrued liability for AROs | $ 100,000 | $ 100,000

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- References No definition available. + Details
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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 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) -URI http://asc.fasb.org/extlink&oid=6392692&loc=d3e7535-110849 + Details
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