CONTRACT REVENUE AND PERCENTAGE-OF-COMPLETION METHOD - Revenues by Geographic Location (Details) - USD ($) $ in Thousands |
3 Months Ended | 12 Months Ended | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
Dec. 31, 2017 |
Sep. 30, 2017 |
Jun. 30, 2017 |
Mar. 31, 2017 |
Dec. 31, 2016 |
Sep. 30, 2016 |
Jun. 30, 2016 |
Mar. 31, 2016 |
Dec. 31, 2017 |
Dec. 31, 2016 |
Dec. 31, 2015 |
|
| Geographic Reporting Disclosure [Line Items] | |||||||||||
| Revenue | $ 37,277 | $ 49,884 | $ 45,868 | $ 37,993 | $ 55,461 | $ 65,384 | $ 81,502 | $ 83,979 | $ 171,022 | $ 286,326 | $ 306,120 |
| United States | |||||||||||
| Geographic Reporting Disclosure [Line Items] | |||||||||||
| Revenue | 171,022 | 245,039 | 287,892 | ||||||||
| International | |||||||||||
| Geographic Reporting Disclosure [Line Items] | |||||||||||
| Revenue | $ 0 | $ 41,287 | $ 18,228 | ||||||||
| X | ||||||||||
- Definition Geographic Reporting Disclosure [Line Items] No definition available.
|
| X | ||||||||||
- Definition Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss). Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- Details
|
| X | ||||||||||
- Details
|