REVENUES (Contract Balances) (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017
Change in Contract with Customer, Liability [Abstract]
Revenues from performance obligations satisfied in previous periods	$ 5,736
Unbilled Revenues
Change in Contract with Customer, Liability [Abstract]
Contract assets	13,522	$ 7,901
Accrued Expenses and Other Current Liabilities
Change in Contract with Customer, Liability [Abstract]
Revenues recognized	3,810
Contract liabilities	4,558	4,498
Other Noncurrent Liabilities
Change in Contract with Customer, Liability [Abstract]
Contract liabilities	$ 224	$ 0

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Amount, before 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.

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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 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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Amount of revenue recognized from performance obligation satisfied or partially satisfied in previous reporting periods. Includes, but is not limited to, change in transaction price.

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