Schedule of Accumulated Other Comprehensive Income (Detail) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018
Accumulated Other Comprehensive Income Loss [Line Items]
Beginning Balance	$ (145,735)	$ (50,976)
Current period other comprehensive income	(1,724)	2,761
Ending Balance	(122,461)	(14,826)
Foreign Currency Translation Adjustments
Accumulated Other Comprehensive Income Loss [Line Items]
Beginning Balance	(53,068)	(48,103)
Changes before reclassifications	(1,724)	2,761
Current period other comprehensive income	(1,724)	2,761
Ending Balance	(54,792)	(45,342)
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	(53,068)	(51,280)
Changes before reclassifications	(1,724)	2,761
Current period other comprehensive income	(1,724)	5,938
Ending Balance	$ (54,792)	(45,342)
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, 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 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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