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Related Party Transactions - Operating Activities - Additional Information (Detail) - USD ($) $ in Millions | 6 Months Ended
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Jun. 30, 2018 | Jun. 30, 2017
Related Party Transaction [Line Items] |  |
Vessel and rig operating expenses | $ 407.0 | $ 437.0
Contract Revenue Cost [Member] | Archer [Member] | Equity Method Investee [Member] |  |
Related Party Transaction [Line Items] |  |
Vessel and rig operating expenses | $ 0.1 | $ 0.2

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- Definition Costs incurred and are directly related to generating contract revenues. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 225 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03.2(e)) -URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688 + Details
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
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- Details
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- Details
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- Details
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