Derivatives and Hedging Instruments - Summary of Effects of Derivatives on Cash Flow Hedging Relationships in Company's Statements of Income, Derivatives Not Designated as Hedging Instruments (Details) - Derivatives not designated as hedging instruments: - Cash Flow Hedging - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Foreign Currency Exchange Contracts | Other income (expense)
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain or (Loss) Recognized in Income on Derivative	$ 2,875	$ 1,990	$ 2,623	$ 7,376
Gain (loss) recognized in earnings after tax and noncontrolling interest	1,000	(200)	900	1,600
Interest rate swap agreements | Interest expense
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain or (Loss) Recognized in Income on Derivative	$ 33	$ 35	$ 110	$ 44