Hedging Instruments (Derivatives Designated In Cash Flow Hedging Relationships) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Foreign Currency Fair Value Hedge Derivative [Line Items]
Cost of revenue	$ 258,250	$ 262,250	$ 524,996	$ 506,709
Foreign currency exchange contracts | Costs of revenue
Foreign Currency Fair Value Hedge Derivative [Line Items]
Amount of gain reclassified from accumulated other comprehensive income into income	$ 1,812	$ 2,509	$ 3,153	$ 3,920