Fair Value - Fair Value of Financial Assets and Liabilities (Detail) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Foreign Currency Exchange Contracts [Member] | Other Noncurrent Assets [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Assets, fair value	$ 16	$ 47
Foreign Currency Exchange Contracts [Member] | Other Current Assets [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Assets, fair value	1,130	1,022
Foreign Currency Exchange Contracts [Member] | Other Current Liabilities [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Liabilities, fair value	996	1,173
Foreign Currency Exchange Contracts [Member] | Other Noncurrent Liabilities [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Liabilities, fair value	1	40
Investments [Member] | Other Noncurrent Assets [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Assets, fair value	4,204	3,863
Quoted Prices in Active Markets for Identical Inputs (Level 1) [Member] | Foreign Currency Exchange Contracts [Member] | Other Noncurrent Assets [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Assets, fair value	0	0
Quoted Prices in Active Markets for Identical Inputs (Level 1) [Member] | Foreign Currency Exchange Contracts [Member] | Other Current Assets [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Assets, fair value	0	0
Quoted Prices in Active Markets for Identical Inputs (Level 1) [Member] | Foreign Currency Exchange Contracts [Member] | Other Current Liabilities [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Liabilities, fair value	0	0
Quoted Prices in Active Markets for Identical Inputs (Level 1) [Member] | Foreign Currency Exchange Contracts [Member] | Other Noncurrent Liabilities [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Liabilities, fair value	0	0
Quoted Prices in Active Markets for Identical Inputs (Level 1) [Member] | Investments [Member] | Other Noncurrent Assets [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Assets, fair value	4,204	3,863
Significant Other Observable Inputs (Level 2) [Member] | Foreign Currency Exchange Contracts [Member] | Other Noncurrent Assets [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Assets, fair value	16	47
Significant Other Observable Inputs (Level 2) [Member] | Foreign Currency Exchange Contracts [Member] | Other Current Assets [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Assets, fair value	1,130	1,022
Significant Other Observable Inputs (Level 2) [Member] | Foreign Currency Exchange Contracts [Member] | Other Current Liabilities [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Liabilities, fair value	996	1,173
Significant Other Observable Inputs (Level 2) [Member] | Foreign Currency Exchange Contracts [Member] | Other Noncurrent Liabilities [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Liabilities, fair value	1	40
Significant Other Observable Inputs (Level 2) [Member] | Investments [Member] | Other Noncurrent Assets [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Assets, fair value	0	0
Significant Unobservable Inputs (Level 3) [Member] | Foreign Currency Exchange Contracts [Member] | Other Noncurrent Assets [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Assets, fair value	0	0
Significant Unobservable Inputs (Level 3) [Member] | Foreign Currency Exchange Contracts [Member] | Other Current Assets [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Assets, fair value	0	0
Significant Unobservable Inputs (Level 3) [Member] | Foreign Currency Exchange Contracts [Member] | Other Current Liabilities [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Liabilities, fair value	0	0
Significant Unobservable Inputs (Level 3) [Member] | Foreign Currency Exchange Contracts [Member] | Other Noncurrent Liabilities [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Liabilities, fair value	0	0
Significant Unobservable Inputs (Level 3) [Member] | Investments [Member] | Other Noncurrent Assets [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Assets, fair value	$ 0	$ 0