Financial Instruments - Additional Information (Detail) (USD $)	3 Months Ended	9 Months Ended
	Sep. 30, 2014	Sep. 30, 2014
Derivative [Line Items]
Amount of losses, net of income taxes, reclassified to earnings from change in fair value of derivatives component of accumulated other comprehensive loss	$ 1,100,000	$ 2,900,000
Estimated reclassification of losses, net of income taxes, from the change in fair value of derivatives component of accumulated other comprehensive loss to earnings during the next twelve months		1,200,000
Interest rate swap agreements [Member]
Derivative [Line Items]
Aggregate notional principal amount of outstanding interest rate swap agreements	283,200,000	283,200,000
Net payments under derivative swap agreements	1,700,000	4,900,000
Commodity Contract [Member]
Derivative [Line Items]
Principal amount of natural gas swap (Mmbtu)	583,000	583,000
Hedged portion of exposure to natural gas price fluctuations (percent)	12.00%	12.00%
Foreign Currency Exchange Rate Risk [Member]
Derivative [Line Items]
Foreign currency (losses) gains of net investment hedges included in accumulated other comprehensive (loss) income	21,300,000	24,600,000
Carrying (Reported) Amount, Fair Value Disclosure [Member]
Derivative [Line Items]
Cash and cash equivalents	145,889,000	145,889,000
Carrying (Reported) Amount, Fair Value Disclosure [Member] | Interest rate swap agreements [Member]
Derivative [Line Items]
Derivative liabilities	2,379,000	2,379,000
Estimate of Fair Value, Fair Value Disclosure [Member]
Derivative [Line Items]
Cash and cash equivalents	145,889,000	145,889,000
Estimate of Fair Value, Fair Value Disclosure [Member] | Interest rate swap agreements [Member]
Derivative [Line Items]
Derivative liabilities	2,379,000	2,379,000
Bank debt [Member] | Carrying (Reported) Amount, Fair Value Disclosure [Member]
Derivative [Line Items]
Long-Term Debt	1,167,030,000	1,167,030,000
Bank debt [Member] | Estimate of Fair Value, Fair Value Disclosure [Member]
Derivative [Line Items]
Long-Term Debt	1,167,030,000	1,167,030,000
5 1/2% Senior Notes [Member] | Carrying (Reported) Amount, Fair Value Disclosure [Member]
Derivative [Line Items]
Long-Term Debt	300,000,000	300,000,000
5 1/2% Senior Notes [Member] | Estimate of Fair Value, Fair Value Disclosure [Member]
Derivative [Line Items]
Long-Term Debt	308,250,000	308,250,000
5% Senior Notes [Member] | Carrying (Reported) Amount, Fair Value Disclosure [Member]
Derivative [Line Items]
Long-Term Debt	500,000,000	500,000,000
5% Senior Notes [Member] | Estimate of Fair Value, Fair Value Disclosure [Member]
Derivative [Line Items]
Long-Term Debt	$ 508,725,000	$ 508,725,000
5.0% Senior Notes due 2020 [Member] | Senior Notes [Member]
Derivative [Line Items]
Senior note interest rate (percent)	5.00%	5.00%
5.5% Senior Notes due 2022 [Member] | Senior Notes [Member]
Derivative [Line Items]
Senior note interest rate (percent)	5.50%	5.50%
Natural Gas [Member] | Minimum [Member] | Commodity Contract [Member]
Derivative [Line Items]
Natural gas fixed price (usd per share)	3.840	3.840
Natural Gas [Member] | Maximum [Member] | Commodity Contract [Member]
Derivative [Line Items]
Natural gas fixed price (usd per share)	4.170	4.170