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Acquisition - Additional Information (Detail) (USD $)	3 Months Ended		0 Months Ended
Acquisition - Additional Information (Detail) (USD $)	Mar. 31, 2015	Mar. 31, 2014	Oct. 01, 2014
Business Acquisition [Line Items]
Revenue	$ 419,537,000us-gaap_SalesRevenueNet	$ 460,983,000us-gaap_SalesRevenueNet
Spezialpapierfabrik Oberschmitten GmbH [Member]
Business Acquisition [Line Items]
Date of acquisition	Oct. 01, 2014
Payment made for acquisition			8,000,000
Revenue			$ 33,000,000