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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

X

- Definition

The amount of advance payments received from customers for goods or services to be provided at a later date.

+ References

No definition available.

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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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

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- Definition

Amount of obligation to transfer good or service to customer for which consideration has been received or is receivable.

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Amount of obligation to transfer good or service to customer for which consideration has been received or is receivable, classified as current.

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Amount of revenue recognized that was previously included in balance of obligation to transfer good or service to customer for which consideration from customer has been received or is due.

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