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Debt - Additional Information (Detail) - USD ($)
9 Months Ended
Sep. 30, 2015
Dec. 31, 2014
Sep. 30, 2014
Line of Credit Facility [Line Items]      
Revolving credit borrowing $ 65,800,000 $ 60,800,000 $ 74,300,000
Letters of credit outstanding 3,000,000    
Capital lease and other obligations 2,100,000 $ 2,900,000 $ 2,000,000
Minimum [Member]      
Line of Credit Facility [Line Items]      
Fall of excess borrowing availability 12,500,000    
Maximum [Member]      
Line of Credit Facility [Line Items]      
Fall of excess borrowing availability 20,000,000    
Revolving Credit Facility [Member]      
Line of Credit Facility [Line Items]      
Asset based senior secured revolving credit $ 160,000,000    
Credit facility maturity date May 28, 2019    
Amortization period on real estate component of borrowing base 12 years 6 months    
Revolving credit borrowing $ 65,800,000    
Weighted average interest rate 2.13%    
Additional committed borrowing capacity $ 68,400,000    
Unused commitment fees 0.25%    
Fixed charge coverage ratio of credit facility 105.00%