Accumulated Other Comprehensive Income/(Loss) - Reclassifications (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Reclassification Adjustment out of Accumulated Other Comprehensive Income on Derivatives [Line Items]
Other operating (income) expense, net	$ 4,393	$ 9,086	$ (3,548)
Comprehensive income (loss) attributable to noncontrolling interest	(14,775)	(9,555)	13,027
Income tax (expense) benefit (Note 9)	(21,681)	(5,064)	$ 859
Accumulated Net Gain (Loss) from Designated or Qualifying Cash Flow Hedges
Reclassification Adjustment out of Accumulated Other Comprehensive Income on Derivatives [Line Items]
Net (gain) loss on cash flow hedges reclassified from accumulated other comprehensive income	(1,968)	583
Reclassification out of Accumulated Other Comprehensive Income | Accumulated Net Gain (Loss) from Designated or Qualifying Cash Flow Hedges
Reclassification Adjustment out of Accumulated Other Comprehensive Income on Derivatives [Line Items]
Comprehensive income (loss) attributable to noncontrolling interest	817	(385)
Income tax (expense) benefit (Note 9)	765	(227)
Reclassification out of Accumulated Other Comprehensive Income | Accumulated Net Gain (Loss) from Designated or Qualifying Cash Flow Hedges | Realized (gain) loss on foreign currency exchange contracts
Reclassification Adjustment out of Accumulated Other Comprehensive Income on Derivatives [Line Items]
Other operating (income) expense, net	(2,631)	759
Reclassification out of Accumulated Other Comprehensive Income | Accumulated Net Gain (Loss) from Designated or Qualifying Cash Flow Hedges | Realized (gain) loss on foreign currency option contracts
Reclassification Adjustment out of Accumulated Other Comprehensive Income on Derivatives [Line Items]
Other operating (income) expense, net	$ (919)	$ 436