Fair Value Measurements (Tables)

12 Months Ended

Dec. 31, 2011

Fair Value Measurements [Abstract]

Fair Value Assets and Liabilities

	Fair Value Measurements at December 31, 2011
Assets	Total		Quoted Prices in Active Markets for Identical Assets (Level 1)		Significant Other Observable Inputs (Level 2)		Significant Unobservable Inputs (Level 3)
Money market funds	$	5,551	$	5,551	$	—	$	—
Hedging contracts		47,720		—		47,720		—
Total	$	53,271	$	5,551	$	47,720	$	—

	Fair Value Measurements at December 31, 2011
Liabilities	Total			Quoted Prices in Active Markets for Identical Liabilities (Level  1)		Significant Other Observable Inputs (Level 2)			Significant Unobservable Inputs (Level 3)
Hedging contracts	($	11,937	)	$	—	($	11,937	)	$	—
Total	($	11,937	)	$	—	($	11,937	)	$	—

	Fair Value Measurements at December 31, 2010
Assets	Total		Quoted Prices in Active Markets for Identical Assets (Level 1)		Significant Other Observable Inputs (Level 2)		Significant Unobservable Inputs (Level 3)
Money market funds	$	7,306	$	7,306	$	—	$	—
Hedging contracts		12,955		—		12,955		—
Total	$	20,261	$	7,306	$	12,955	$	—

	Fair Value Measurements at December 31, 2010
Liabilities	Total			Quoted Prices in Active Markets for Identical Liabilities (Level  1)		Significant Other Observable Inputs (Level 2)			Significant Unobservable Inputs (Level 3)
Hedging contracts	($	35,750	)	$	—	($	35,750	)	$	—
Total	($	35,750	)	$	—	($	35,750	)	$	—