Schedule of Accumulated Other Comprehensive Income (Detail) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Accumulated Other Comprehensive Income Loss [Line Items]
Beginning Balance			$ (145,735)
Foreign currency translation loss	$ (4,044)	$ (729)	(4,647)	$ (3,509)
Current period other comprehensive income	(4,044)	(729)	(4,647)	(3,509)
Ending Balance	(164,492)	(74,909)	(164,492)	(74,909)
Foreign Currency Translation Adjustments
Accumulated Other Comprehensive Income Loss [Line Items]
Beginning Balance			(53,068)	(48,103)
Foreign currency translation loss			(4,647)	(3,509)
Current period other comprehensive income			(4,647)	(3,509)
Ending Balance	(57,715)	(51,612)	(57,715)	(51,612)
Unrealized Losses of Available for Sale Securities
Accumulated Other Comprehensive Income Loss [Line Items]
Beginning Balance				(3,177)
Current period other comprehensive income				3,177
Unrealized Losses of Available for Sale Securities \| ASU 2016-01
Accumulated Other Comprehensive Income Loss [Line Items]
Cumulative adjustment for adoption of ASU 2016-01				3,177
AOCI Attributable to Parent
Accumulated Other Comprehensive Income Loss [Line Items]
Beginning Balance	(53,671)	(50,883)	(53,068)	(51,280)
Foreign currency translation loss			(4,647)	(3,509)
Current period other comprehensive income			(4,647)	(332)
Ending Balance	$ (57,715)	$ (51,612)	$ (57,715)	(51,612)
AOCI Attributable to Parent \| ASU 2016-01
Accumulated Other Comprehensive Income Loss [Line Items]
Cumulative adjustment for adoption of ASU 2016-01				$ 3,177

Other comprehensive income (loss) net of tax cumulative effect of accounting change.

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Amount after tax and reclassification adjustments of gain (loss) on foreign currency translation adjustments, foreign currency transactions designated and effective as economic hedges of a net investment in a foreign entity and intra-entity foreign currency transactions that are of a long-term-investment nature.

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Amount after tax and 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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