Segment Disclosures - Narrative (Details) |
3 Months Ended | 12 Months Ended | |
|---|---|---|---|
|
Mar. 31, 2018
segment
|
Dec. 31, 2017
segment
|
Dec. 31, 2015
jacket
|
|
| Segment Reporting [Abstract] | |||
| Number of operating segments | 4 | ||
| Number of corporate non-operating segments | 1 | ||
| Number of jackets and piles constructed | jacket | 5 | ||
| X | ||||||||||
- Definition Number Of Corporate Non-Operating Segments No definition available.
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| X | ||||||||||
- Definition Number Of Jackets And Piles Constructed No definition available.
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| X | ||||||||||
- Definition Number of operating segments. An operating segment is a component of an enterprise: (a) that engages in business activities from which it may earn revenues and incur expenses (including revenues and expenses relating to transactions with other components of the same enterprise), (b) whose operating results are regularly reviewed by the enterprise's chief operating decision maker to make decisions about resources to be allocated to the segment and assess its performance, and (c) for which discrete financial information is available. An operating segment may engage in business activities for which it has yet to earn revenues, for example, start-up operations may be operating segments before earning revenues. No definition available.
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| X | ||||||||||
- References No definition available.
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