Derivatives (Details 3) (USD $)	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Derivatives instruments designated as hedging instruments | Fair value hedges
Gain (loss) on derivative
Realized and Unrealized Gain (Loss) on Hedge	$ (20,869,000)	$ (21,357,000)	$ (3,262,000)
Derivatives instruments designated as hedging instruments | Fair value hedges | Hedged items
Gain (loss) on derivative
Realized and Unrealized Gain (Loss) on Hedged Item	24,510,000	33,175,000	13,128,000
Derivatives instruments designated as hedging instruments | Fair value hedges | Revenue | Hedged item commitments
Gain (loss) on derivative
Realized and Unrealized Gain (Loss) on Hedged Item	(201,000)	(12,973,000)	(7,494,000)
Derivatives instruments designated as hedging instruments | Fair value hedges | Cost of revenue | Hedged item commitments
Gain (loss) on derivative
Realized and Unrealized Gain (Loss) on Hedged Item	739,000	7,771,000	(797,000)
Derivatives instruments designated as hedging instruments | Fair value hedges | Cost of revenue | Hedged item inventories
Gain (loss) on derivative
Realized and Unrealized Gain (Loss) on Hedged Item	23,972,000	38,377,000	21,419,000
Derivatives instruments designated as hedging instruments | Cash flow hedges
Gain (loss) on derivative
Amount of Gain (Loss) Recognized in Accumulated Other Comprehensive Income (Effective Portion)	196,000		1,718,000
Amount of Gain (Loss) Reclassified from Accumulated Other Comprehensive Income (Effective Portion)	48,000		1,026,000
Realized net gain (loss) being reclassified from accumulated other comprehensive income to cost of revenue due to ineffective derivative instrument			700,000
Derivatives instruments not designated as hedging instruments
Gain (loss) on derivative
Realized and Unrealized Gain (Loss)	13,645,000	18,687,000	5,920,000
Commodity contracts | Derivatives instruments designated as hedging instruments | Fair value hedges | Revenue
Gain (loss) on derivative
Realized and Unrealized Gain (Loss) on Hedge	265,000	11,608,000	10,040,000
Commodity contracts | Derivatives instruments designated as hedging instruments | Fair value hedges | Cost of revenue
Gain (loss) on derivative
Realized and Unrealized Gain (Loss) on Hedge	(1,417,000)	(6,926,000)	(739,000)
Commodity contracts | Derivatives instruments not designated as hedging instruments | Revenue
Gain (loss) on derivative
Realized and Unrealized Gain (Loss)	14,967,000	14,283,000	4,385,000
Commodity contracts | Derivatives instruments not designated as hedging instruments | Cost of revenue
Gain (loss) on derivative
Realized and Unrealized Gain (Loss)	3,333,000	3,137,000	(1,001,000)
Foreign currency contracts | Derivatives instruments designated as hedging instruments | Cash flow hedges
Gain (loss) on derivative
Amount of Gain (Loss) Recognized in Accumulated Other Comprehensive Income (Effective Portion)			1,799,000
Foreign currency contracts | Derivatives instruments designated as hedging instruments | Cash flow hedges | Revenue
Gain (loss) on derivative
Amount of Gain (Loss) Reclassified from Accumulated Other Comprehensive Income (Effective Portion)			1,107,000
Foreign currency contracts | Derivatives instruments not designated as hedging instruments | Revenue
Gain (loss) on derivative
Realized and Unrealized Gain (Loss)	(2,384,000)	1,653,000
Foreign currency contracts | Derivatives instruments not designated as hedging instruments | Other income (expense), net
Gain (loss) on derivative
Realized and Unrealized Gain (Loss)	(2,271,000)	(386,000)	2,536,000
Commodity contracts. | Derivatives instruments designated as hedging instruments | Fair value hedges | Cost of revenue
Gain (loss) on derivative
Realized and Unrealized Gain (Loss) on Hedge	(19,717,000)	(26,039,000)	(12,563,000)
Foreign exchange contracts... | Derivatives instruments designated as hedging instruments | Cash flow hedges
Gain (loss) on derivative
Amount of Gain (Loss) Recognized in Accumulated Other Comprehensive Income (Effective Portion)	196,000		(81,000)
Foreign exchange contracts... | Derivatives instruments designated as hedging instruments | Cash flow hedges | Other income (expense), net
Gain (loss) on derivative
Amount of Gain (Loss) Reclassified from Accumulated Other Comprehensive Income (Effective Portion)	$ 48,000		$ (81,000)