Summary of Outstanding Derivative Instruments on Gross Basis as Recorded in Consolidated Balance Sheets (Detail) - Undesignated Hedges - USD ($) $ in Thousands		Sep. 30, 2017	Dec. 31, 2016
Derivatives, Fair Value [Line Items]
Notional Amounts		$ 1,418	$ 1,146
Derivative Liabilities		2	8
Forward foreign currency contracts
Derivatives, Fair Value [Line Items]
Notional Amounts		1,418	1,146
Derivative Liabilities	[1]	$ 2	$ 8

[1] Other accrued liabilities