STOCKHOLDERS' EQUITY - CHANGES IN ACCUMULATED OTHER COMPREHENSIVE INCOME (LOSS) (Detail) $ in Thousands	9 Months Ended
Sep. 30, 2018 USD ($)
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax [Abstract]
Beginning balance	$ 99
Other Comprehensive Income (Loss), Net of Tax [Abstract]
Other comprehensive income before reclassifications	8
Amounts reclassified from accumulated other comprehensive income	0
Net current period other comprehensive income	8
Ending balance	107
Unrealized Gains and Losses on Short-term Investments
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax [Abstract]
Beginning balance	(23)
Other Comprehensive Income (Loss), Net of Tax [Abstract]
Other comprehensive income before reclassifications	8
Amounts reclassified from accumulated other comprehensive income	0
Net current period other comprehensive income	8
Ending balance	(15)
Foreign Currency Items
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax [Abstract]
Beginning balance	122
Other Comprehensive Income (Loss), Net of Tax [Abstract]
Other comprehensive income before reclassifications	0
Amounts reclassified from accumulated other comprehensive income	0
Net current period other comprehensive income	0
Ending balance	$ 122

Amount after tax, before reclassification adjustments of other comprehensive income (loss).

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Amount after tax and reclassification adjustments of other comprehensive income (loss).

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Amount after tax of reclassification adjustments of other comprehensive income (loss).

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Amount of stockholders' equity (deficit), net of receivables from officers, directors, owners, and affiliates of the entity, attributable to both the parent and noncontrolling interests. Amount excludes temporary equity. Alternate caption for the concept is permanent equity.

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