Change in Carrying Amount of Goodwill (Detail) $ in Thousands	9 Months Ended
	Sep. 30, 2018 USD ($)
Goodwill [Line Items]
Balance as of January 1,	$ 72,952	[1]
Currency translation adjustments	(55)
Balance as of September 30,	$ 72,897	[1]

[1] On January 1, 2018, the Company adopted the ASC 606 revenue recognition standard and has adjusted prior periods to conform. See Note 2. "New Accounting Pronouncements" for additional information.