Acquisition - Additional Information (Detail) (USD $)	0 Months Ended	3 Months Ended		6 Months Ended			6 Months Ended		3 Months Ended	6 Months Ended	12 Months Ended
	Apr. 30, 2013	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013	Dec. 31, 2013	Jun. 30, 2014 Minimum [Member]	Jun. 30, 2014 Maximum [Member]	Jun. 30, 2014 Dresden Papier GmbH [Member]	Jun. 30, 2014 Dresden Papier GmbH [Member]	Dec. 31, 2013 Dresden Papier GmbH [Member] Employees t
Business Acquisition [Line Items]
Payment made for acquisition, net of cash acquired	$ 211,000,000			$ 0	$ 210,911,000
Revenue		446,131,000	426,391,000	907,114,000	832,681,000				79,600,000	38,300,000	158,600,000
Number of employees											146
Manufacturing capacity											72,800
Date of acquisition										Apr. 30, 2013
Useful life of property plant and equipment							5 years	30 years
Remaining useful life of intangible assets				17 years
Goodwill		94,826,000		94,826,000		95,948,000			74,870,000	74,870,000
Intangible assets		87,596,000		87,596,000					87,596,000	87,596,000
Identifiable intangible assets				9,800,000
Operating income		$ 10,605,000	$ 6,331,000	$ 32,903,000	$ 30,292,000				$ 17,100,000	$ 8,200,000