Derivative Instruments - Outstanding Forward Contracts Table (Detail) - Not Designated as Hedging Instrument € in Thousands, ₩ in Thousands, ¥ in Thousands, $ in Thousands, $ in Thousands, $ in Thousands, $ in Thousands	Jun. 30, 2019 EUR (€)	Jun. 30, 2019 CAD ($)	Jun. 30, 2019 SGD ($)	Jun. 30, 2019 JPY (¥)	Jun. 30, 2019 KRW (₩)	Jun. 30, 2019 TWD ($)	Jun. 30, 2019 USD ($)	Dec. 31, 2018 EUR (€)	Dec. 31, 2018 CAD ($)	Dec. 31, 2018 SGD ($)	Dec. 31, 2018 JPY (¥)	Dec. 31, 2018 KRW (₩)	Dec. 31, 2018 TWD ($)	Dec. 31, 2018 USD ($)
Euro Member Countries, Euro
Derivative [Line Items]
Outstanding forward contracts	€ 19,000						$ 21,681	€ 23,000						$ 26,330
Japanese Yen
Derivative [Line Items]
Outstanding forward contracts				¥ 400,000			3,717				¥ 380,000			3,459
United Kingdom, Pounds
Derivative [Line Items]
Outstanding forward contracts				2,400			3,055				2,500			3,204
Hungary, Forint
Derivative [Line Items]
Outstanding forward contracts				¥ 900,000			3,178				¥ 750,000			2,685
Korean Won
Derivative [Line Items]
Outstanding forward contracts					₩ 3,550,000		3,072					₩ 3,125,000		2,808
Taiwanese Dollar
Derivative [Line Items]
Outstanding forward contracts						$ 50,000	1,617						$ 55,000	1,807
Canada, Dollars
Derivative [Line Items]
Outstanding forward contracts		$ 1,100					841		$ 990					726
Singapore, Dollars
Derivative [Line Items]
Outstanding forward contracts			$ 0				$ 0			$ 700				$ 514