Hedging - Cash Flow Hedging Instruments (Details) - Cash flow hedging instruments - USD ($) $ in Thousands		3 Months Ended		9 Months Ended
		Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Derivative Instruments, Gain (Loss) [Line Items]
Gain (loss) recognized in OCI on derivative (effective portion)		$ (620)	$ 19,072	$ 15,384	$ 22,467
Gain (loss) reclassified from accumulated OCI into income (effective portion)	[1]	4,116	721	22,683	(1,090)
Gain (loss) recognized in income on derivative (ineffective portion)	[1]	11	(230)	78	(657)
Currency Hedge Portfolio
Derivative Instruments, Gain (Loss) [Line Items]
Gain (loss) recognized in OCI on derivative (effective portion)		341	23,983	15,472	26,757
Gain (loss) reclassified from accumulated OCI into income (effective portion)	[1]	7,876	1,543	38,683	(504)
Gain (loss) recognized in income on derivative (ineffective portion)	[1]	0	0	0	0
Bunker Fuel Forward Contracts
Derivative Instruments, Gain (Loss) [Line Items]
Gain (loss) recognized in OCI on derivative (effective portion)		(961)	(4,911)	(88)	(4,290)
Gain (loss) reclassified from accumulated OCI into income (effective portion)	[1]	(3,760)	(822)	(16,000)	(586)
Gain (loss) recognized in income on derivative (ineffective portion)	[1]	$ 11	$ (230)	$ 78	$ (657)

[1] Both the gain (loss) reclassified from "AOCI" into income (effective portion) and the gain (loss) recognized in income on derivative (ineffective portion), if any, are included in "Net sales" for the currency hedge portfolio and "Cost of sales" for bunker fuel forward contracts.