Fair Value - Fair Value of Financial Assets and Liabilities (Detail) - USD ($) $ in Thousands	Jun. 30, 2018	Dec. 31, 2017
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	$ 77	$ 16
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	563	1,130
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	819	996
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	45	1
Investments [Member] | Other Noncurrent Assets [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Assets, fair value	4,064	4,204
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	4,064	4,204
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	77	16
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	563	1,130
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	819	996
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	45	1
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