ACCOUNTS RECEIVABLE, NET (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Accounts receivable, net
Accounts receivable, gross	$ 38,748	$ 47,349
Less: Allowance for doubtful accounts	(10,114)	(10,883)
Total	28,634	36,466
Billed
Accounts receivable, net
Accounts receivable, gross	27,968	35,590
Unbilled
Accounts receivable, net
Accounts receivable, gross	$ 10,780	$ 11,759

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

No definition available.

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Amounts due from customers or clients, within one year of the balance sheet date (or the normal operating cycle, whichever is longer) for goods or services (including trade receivables) that have been delivered or sold in the normal course of business.

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A valuation allowance for trade and other receivables due to an Entity within one year (or the normal operating cycle, whichever is longer) that are expected to be uncollectible.

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