RECEIVABLES, CONTRACT ASSETS, AND DEFERRED REVENUE - Summary of Contract Assets and Deferred Revenue (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
Receivables [Abstract]
Contract assets	$ 3,770	$ 3,711
Long-term contract assets	2,190	2,543
Total contract assets	5,960	6,254
Deferred revenue	169,009	185,145
Long-term deferred revenue	4,342	5,344
Total deferred revenue	$ 173,351	$ 190,489

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.

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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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Carrying amount as of the balance sheet date of unearned revenue or income, not otherwise specified in the taxonomy, which is expected to be taken into income during the current period and current obligations not separately disclosed in the balance sheet (other liabilities, current).

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