BASIS OF PRESENTATION AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Impact of Adoption on Unaudited Condensed Consolidated Balance Sheet (Details) - USD ($) $ in Thousands	Jun. 30, 2018	Dec. 31, 2017
Balance Sheet:
Accounts receivable, net	$ 12,564	$ 6,105
Deferred costs on contracts	489	2,107
Accrued liabilities	7,444	6,311
Income and other taxes payable	5,268	7,887
Accumulated deficit	(168,726)	$ (133,306)
Accounting Standards Update 2014-09 \| Balances Without Adoption of ASU 2014-09
Balance Sheet:
Accounts receivable, net	11,193
Deferred costs on contracts	489
Accrued liabilities	6,194
Income and other taxes payable	5,223
Accumulated deficit	(168,802)
Accounting Standards Update 2014-09 \| Impact of Adoption of ASU 2014-09
Balance Sheet:
Accounts receivable, net	1,371
Accrued liabilities	1,250
Income and other taxes payable	45
Accumulated deficit	$ 76

Amount 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, reduced to the estimated net realizable fair value by an allowance established by the entity of the amount it deems uncertain of collection.

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Carrying value as of the balance sheet date of obligations incurred and payable, pertaining to costs that are statutory in nature, are incurred on contractual obligations, or accumulate over time and for which invoices have not yet been received or will not be rendered. Examples include taxes, interest, rent and utilities. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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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, classified as current.

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Carrying value as of the balance sheet date of obligations incurred and payable for statutory income, sales, use, payroll, excise, real, property and other taxes. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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