Financial Instruments - Additional Information (Detail)	3 Months Ended			3 Months Ended		3 Months Ended			3 Months Ended
	Mar. 31, 2012 USD ($)	Mar. 31, 2012 Accrued liabilities USD ($)	Mar. 31, 2012 Other liabilities USD ($)	Mar. 31, 2012 Interest rate swap agreements USD ($)	Mar. 31, 2012 Interest rate swap agreements EUR (€)	Mar. 31, 2012 Natural gas swap agreements USD ($) MMBtu	Mar. 31, 2012 Natural gas swap agreements Minimum	Mar. 31, 2012 Natural gas swap agreements Maximum	Mar. 31, 2012 Foreign Currency Exchange Rate Risk USD ($)
Derivative [Line Items]
Fair value of total outstanding swap agreements	$ 12,400,000	$ 5,400,000	$ 7,000,000
Amount of loss reclassified to earnings from derivatives component of accumulated other comprehensive (loss) income	800,000
Estimated amount of loss to be reclassified to earnings from derivatives component of accumulated other comprehensive (loss) income during the next twelve months	2,900,000
Aggregate notional principal amount of outstanding interest rate swap agreements					105,000,000
Percentage of hedged estimated twelve month exposure to fluctuations in natural gas prices						16.00%
Net payments under derivative swap agreements				1,000,000		500,000
Aggregate notional principal amount of natural gas swap agreements						707,000
Natural gas fixed prices per MMBtu							2.587	4.814
Foreign currency losses of net investment hedges included in accumulated other comprehensive (loss) income									$ 10,400,000