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REVENUE, Contract Assets and Contract Liabilities (Details) - USD ($) $ in Thousands | 6 Months Ended |
--- | --- | ---
Jun. 30, 2018 | Dec. 31, 2017
Contract with Customer, Asset and Liability [Abstract] |  |
Contract assets - current (unbilled receivable) | $ 15,587 | $ 0
Contract liabilities - current (deferred revenue) | 1,609 |
Deferred Revenue [Roll Forward] |  |
Balance, beginning of period | 855 |
New advance payments received | 3,928 |
Recognized as revenue during period | (3,174) |
Balance, end of period | $ 1,609 |
ASU 2014-09 [Member] |  |
Contract with Customer, Asset and Liability [Abstract] |  |
Contract assets - current (unbilled receivable) |  | 14,536
Contract liabilities - current (deferred revenue) |  | $ 855

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- Definition Amount, after allowance for credit loss, of right to consideration in exchange for good or service transferred to customer when right is conditioned on something other than passage of time, classified as current. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 606 -SubTopic 10 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=82913815&loc=SL49130531-203044 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 606 -SubTopic 10 -Section 45 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=82913815&loc=SL49130533-203044 + Details
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