Fair Values of Derivative Financial Instruments Included in Consolidated Balance Sheets (Detail) - Fair Value, Observable inputs, Level 2 - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016
Designated as Hedging Instrument | Interest Rate Contract | Deferred rent & other long-term liabilities
Derivatives, Fair Value [Line Items]
Fair Value of Derivative Liabilities		$ 3
Designated as Hedging Instrument | Interest Rate Contract | Accrued expenses
Derivatives, Fair Value [Line Items]
Fair Value of Derivative Liabilities		4
Designated as Hedging Instrument | Interest Rate Contract | Prepaid expenses
Derivatives, Fair Value [Line Items]
Fair Value of Derivative Liabilities	$ 18
Not Designated as Hedging Instrument | Foreign exchange contract | Prepaid expenses and other current assets
Derivatives, Fair Value [Line Items]
Fair Value of Derivative Assets		$ 924
Not Designated as Hedging Instrument | Foreign exchange contract | Accrued expenses
Derivatives, Fair Value [Line Items]
Fair Value of Derivative Assets	$ 814