Accumulated Other Comprehensive Income (Loss) (Details 2) (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Amounts reclassified out of accumulated other comprehensive loss
Cost of products sold (excluding depreciation)	$ (93,001)	$ (98,544)	$ (279,473)	$ (294,826)
Restructuring	87	(7,958)	129	(7,958)
Income (loss) before income tax provision (benefit)	17,358	(4,649)	51,230	23,352
Tax (expense) or benefit	(5,473)	196	(16,561)	(9,183)
Net income (loss)	11,885	(4,453)	34,669	14,169
Amount Reclassified from Accumulated Other Comprehensive Loss
Amounts reclassified out of accumulated other comprehensive loss
Net income (loss)	(461)		(644)
Gains and losses on cash flow hedges | Amount Reclassified from Accumulated Other Comprehensive Loss
Amounts reclassified out of accumulated other comprehensive loss
Income (loss) before income tax provision (benefit)	269		293
Tax (expense) or benefit	(122)		(141)
Net income (loss)	147		152
Gains and losses on cash flow hedges | Amount Reclassified from Accumulated Other Comprehensive Loss | Foreign Exchange Contracts
Amounts reclassified out of accumulated other comprehensive loss
Cost of products sold (excluding depreciation)	339		769
Gains and losses on cash flow hedges | Amount Reclassified from Accumulated Other Comprehensive Loss | Natural gas forward contracts
Amounts reclassified out of accumulated other comprehensive loss
Cost of products sold (excluding depreciation)	(70)		(476)
Pension Benefit Adjustments | Amount Reclassified from Accumulated Other Comprehensive Loss
Amounts reclassified out of accumulated other comprehensive loss
Prior-service costs	(18)		(56)
Actuarial losses	(962)		(2,882)
Income (loss) before income tax provision (benefit)	(980)		(2,938)
Tax (expense) or benefit	372		1,110
Net income (loss)	(608)		(1,828)
Foreign Currency Translation Adjustments | Amount Reclassified from Accumulated Other Comprehensive Loss
Amounts reclassified out of accumulated other comprehensive loss
Restructuring			1,032
Income (loss) before income tax provision (benefit)			1,032
Net income (loss)			$ 1,032