Financial Instruments - Additional Information (Detail)		12 Months Ended					12 Months Ended										12 Months Ended						12 Months Ended
	Dec. 31, 2011	Dec. 31, 2011 Sales Revenue, Goods, Net Entity	Dec. 31, 2010 Sales Revenue, Goods, Net Entity	Dec. 31, 2009 Sales Revenue, Goods, Net Entity	Dec. 31, 2011 Accounts Receivable	Dec. 31, 2010 Accounts Receivable	Dec. 31, 2011 Interest rate swap agreements USD ($)	Dec. 31, 2010 Interest rate swap agreements USD ($)	Dec. 31, 2009 Interest rate swap agreements USD ($)	Dec. 31, 2011 Interest rate swap agreements EUR (€)	Dec. 31, 2010 Interest rate swap agreements EUR (€)	Dec. 31, 2011 Interest rate swap agreements Accrued liabilities USD ($)	Dec. 31, 2010 Interest rate swap agreements Accrued liabilities USD ($)	Dec. 31, 2011 Interest rate swap agreements Other liabilities USD ($)	Dec. 31, 2010 Interest rate swap agreements Other liabilities USD ($)	Dec. 31, 2011 Euro Interest Rate Swap	Dec. 31, 2011 Natural gas swap agreements USD ($) MMBtu	Dec. 31, 2010 Natural gas swap agreements USD ($) MMBtu	Dec. 31, 2009 Natural gas swap agreements USD ($)	Dec. 31, 2011 Natural gas swap agreements Minimum	Dec. 31, 2011 Natural gas swap agreements Maximum	Dec. 31, 2011 Natural gas swap agreements Accrued liabilities USD ($)	Dec. 31, 2011 Foreign Currency Exchange Rate Risk USD ($)	Dec. 31, 2010 Foreign Currency Exchange Rate Risk USD ($)	Dec. 31, 2009 Foreign Currency Exchange Rate Risk USD ($)
Derivative [Line Items]
Aggregate notional principal amount of outstanding interest rate swap agreements										€ 105,000,000	€ 125,000,000
Fixed interest rate on agreement																4.10%
Agreement maturity year																2014
Net payments under derivative swap agreements							4,700,000	7,600,000	8,000,000								600,000	1,200,000	2,800,000
Effective interest rate on Euro term loans										4.00%
Fair value of total outstanding swap agreements												3,900,000	4,800,000	7,300,000	6,900,000							800,000
Percentage of hedged estimated twelve month exposure to fluctuations in natural gas prices																	29.00%	39.00%	33.00%
Aggregate notional principal amount of natural gas swap agreements																	700,000	1,000,000
Natural gas fixed prices per MMBtu																				4.07	5.62
Foreign currency gains of net investment hedges included in accumulated other comprehensive (loss) income, net of deferred tax benefit																							$ 15,300,000	$ 14,900,000	$ 3,000,000
Number of customers		3	3	3
Concentration risk, percentage	99.00%	27.10%	30.50%	30.90%	20.70%	22.00%