REVENUE RECOGNITION - Schedule of Assets and Liabilities Associated with Contracts from Customers (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Disaggregation Of Revenue [Line Items]
Accounts receivable	$ 82,592	$ 60,452
Short-term deferred revenue	99,565	97,333
Long-term deferred revenue	49,866	$ 47,529
Other Current Assets [Member]
Disaggregation Of Revenue [Line Items]
Short-term unbilled receivables	$ 2,757

Amount, after allowance for credit loss, of right to consideration from customer for product sold and service rendered in normal course of business, classified as current.

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

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