Retirement Plans - Defined Contribution Plans - Additional Information (Detail) (Salaried and Quinnesec hourly employees defined contribution plan, USD $)
In Millions, unless otherwise specified
12 Months Ended
Dec. 31, 2014
Dec. 31, 2013
Dec. 31, 2012
Salaried and Quinnesec hourly employees defined contribution plan
     
Defined Contribution Plan [Line Items]      
Defined contribution plan expense $ 4.9 $ 4.8 $ 5.6