ACCOUNTS RECEIVABLE, NET (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Accounts receivable, net
Accounts receivable, gross	$ 71,145	$ 47,349
Less: Allowance for doubtful accounts	(7,062)	(10,883)
Total	64,083	36,466
Billed
Accounts receivable, net
Accounts receivable, gross	58,467	35,590
Unbilled
Accounts receivable, net
Accounts receivable, gross	$ 12,678	$ 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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