Accumulated Other Comprehensive Income (Loss) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Accumulated Other Comprehensive Income [Roll Forward]
Balace at beginning of period	$ (3,119)
Reversal of accumulated unrecognized gain on retiree medical plan	0	0	(137)
Reclassification of hedging activities into earnings, net of tax	(80)	2,315	615
Balance at end of period	(93,399)	(3,119)
Accumulated Other Comprehensive Income (Loss) [Member]
Accumulated Other Comprehensive Income [Roll Forward]
Balace at beginning of period	(3,119)	(16,969)	(29,983)
Reversal of accumulated unrecognized gain on retiree medical plan	0	0	(137)
Reclassification of hedging activities into earnings, net of tax	(80)	2,315	615
Current period credit (charge)	(90,200)	11,535	12,536
Balance at end of period	(93,399)	(3,119)	(16,969)
Foreign Currenty Translation [Member]
Accumulated Other Comprehensive Income [Roll Forward]
Balace at beginning of period	11,743	(5,288)	(18,029)
Current period credit (charge)	(62,580)	17,031	12,741
Balance at end of period	(50,837)	11,743	(5,288)
Unrealized Gains and Losses on Cash Flow Hedging Derivatives [Member]
Accumulated Other Comprehensive Income [Roll Forward]
Balace at beginning of period	(393)	24	0
Reclassification of hedging activities into earnings, net of tax	(80)	2,315	615
Current period credit (charge)	(3,581)	(2,732)	(591)
Balance at end of period	(4,054)	(393)	24
Pension and Post-Retirement Obligation [Member]
Accumulated Other Comprehensive Income [Roll Forward]
Balace at beginning of period	(14,469)	(11,705)	(11,954)
Reversal of accumulated unrecognized gain on retiree medical plan			(137)
Current period credit (charge)	(24,039)	(2,764)	386
Balance at end of period	$ (38,508)	$ (14,469)	$ (11,705)