Foreign Currency Exchange Contracts and Hedging (Narrative) (Details) - Foreign currency exchange contracts $ in Thousands	1 Months Ended	3 Months Ended		9 Months Ended
	Feb. 09, 2017 USD ($) counterparty	Dec. 31, 2016 USD ($) counterparty	Dec. 31, 2015 USD ($)	Dec. 31, 2016 USD ($) counterparty	Dec. 31, 2015 USD ($)
Derivatives designated as cash flow hedges
Summary of the effect of derivative instruments on the consolidated statements of income
Amount of gain (loss) recognized in other comprehensive loss on derivatives (effective portion)		$ 2,053	$ 1,392	$ 6,957	$ (106)
Amount of gain (loss) reclassified from accumulated other comprehensive loss into income (effective portion)		4,294	(892)	5,970	(1,686)
Amount of gain excluded from effectiveness testing		142	(32)	497	34
Designated as hedging instrument
Foreign currency exchange contracts and hedging
Derivative notional amount		19,000		19,000
Derivative, settled during period, notional amount		47,000		88,000
Non-designated derivatives
Foreign currency exchange contracts and hedging
Derivative notional amount		$ 5,000		$ 5,000
Number of counterparties in derivative contracts | counterparty		4		4
Remaining maturity of foreign currency derivatives (in months)				3 months
Derivative, entered into and settled during period, notional amount		$ 74,000		$ 197,000
Summary of the effect of derivative instruments on the consolidated statements of income
Amount of (gain) loss recognized in income on derivatives		$ 4,038	$ 1,014	$ (3,157)	$ 553
Subsequent event | Non-designated derivatives
Foreign currency exchange contracts and hedging
Derivative notional amount	$ 61,400
Number of counterparties in derivative contracts | counterparty	5
Remaining maturity of foreign currency derivatives (in months)	3 months