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Investments - Additional Information (Detail) - USD ($) $ in Thousands			3 Months Ended		9 Months Ended
	Jul. 07, 2017	Jun. 27, 2017	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017	Jan. 31, 2018	Dec. 31, 2017
Equity Method Investments [Line Items]
Gain (loss) from equity method investment					$ (1,051)	$ (226)
Investment		$ 950				950
Bi-PA
Equity Method Investments [Line Items]
Equity investment ownership position			15.00%		15.00%
Impairment on the investment					$ 0
Profeng Australia, Pty Ltd
Equity Method Investments [Line Items]
Joint venture, consideration	$ 1,900
TyraTech Inc.
Equity Method Investments [Line Items]
Equity investment ownership position							34.38%	15.11%
Gain (loss) from equity method investment			$ (352)	$ (29)	$ (795)	(140)
Hong Kong JV
Equity Method Investments [Line Items]
Equity investment ownership position			50.00%		50.00%
Gain (loss) from equity method investment			$ (182)	$ (86)	$ (256)	$ (86)