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CONTRACT REVENUE AND PERCENTAGE-OF-COMPLETION METHOD - Narrative (Details) $ in Thousands | 3 Months Ended | 12 Months Ended
--- | --- | ---
Dec. 31, 2017 USD ($) vessel | Dec. 31, 2017 USD ($) vessel | Dec. 31, 2016 USD ($) | Dec. 31, 2015 USD ($)
Revenue from External Customer [Line Items] |  |  |  |
Loss on contracts |  | $ 36,500 | $ 1,800 | $ 33,900
Loss related to cost overruns and re-work | $ 22,500 | $ 34,500 |  |
Number of multi-purpose service vessels being constructed | vessel | 2 | 2 |  |
Estimated liquidated damages | $ 233 |  |  |
Percentage of revenue related to fabricated structures for delivery outside U.S |  | 0.00% | 14.00% | 6.00%
Pass-through costs as a percentage of revenue |  | 53.10% | 36.50% | 44.40%
Number of offshore service vessels being constructed | vessel | 2 | 2 |  |
Large Deepwater Project, Recently Delivered |  |  |  |
Revenue from External Customer [Line Items] |  |  |  |
Loss on contracts |  |  |  | $ 24,500
Fabrication Facilities |  |  |  |
Revenue from External Customer [Line Items] |  |  |  |
Loss on contract due to labor rate changes |  |  |  | $ 9,400
Maximum |  |  |  |
Revenue from External Customer [Line Items] |  |  |  |
Estimated liquidated damages |  | $ 11,200 |  |

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- Definition Losses recognized in the current period on contracts which are expected to generate losses, which are probable and can be reasonably estimated, in a future period. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 450 -SubTopic 20 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=82911808&loc=d3e14326-108349 Reference 2: 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) -URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688 + Details
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