Fair Value Measurement - Additional Information (Detail) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other non-operating items, net	$ 8,200,000	$ (1,900,000)	$ 8,600,000	$ (6,900,000)
Asset impairment charges	0		0
Derivatives Designated as Hedging Instruments
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative instruments gain (loss) reclassified from accumulated OCI, recognized in income Statement	200,000		200,000
Derivatives designated as hedging instruments outstanding		0		0
Gain (loss) recognized in consolidated statement of net income		0		0
Derivatives Designated as Hedging Instruments | Foreign Exchange Forward | Cash Flow Hedging | Less Than One Year
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Gain (loss) recognized in OCI on derivative effective portion, net	900,000		600,000
Derivatives Designated as Hedging Instruments | Foreign Exchange Forward | Cash Flow Hedging | Less Than Two Years
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Gain (loss) recognized in OCI on derivative effective portion, net	300,000		200,000
Not Designated as Hedging Instrument
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other non-operating items, net	$ 600,000	$ 800,000	$ (1,000,000)	$ 1,900,000