Quarterly report pursuant to Section 13 or 15(d)

Business and Credit Concentrations - Company's Top Five Manufacturers Produced (Detail)

v3.5.0.2
Business and Credit Concentrations - Company's Top Five Manufacturers Produced (Detail) - Cost of Goods, Total [Member] - Supplier Concentration Risk [Member]
 3 Months Ended 6 Months Ended
Jun. 30, 2016
Jun. 30, 2015
Jun. 30, 2016
Jun. 30, 2015
Concentration Risk [Line Items]        
Percentage of total production 56.00% 58.10% 55.50% 58.20%
Manufacturer One [Member]        
Concentration Risk [Line Items]        
Percentage of total production 25.10% 32.80% 25.60% 33.50%
Manufacturer Two [Member]        
Concentration Risk [Line Items]        
Percentage of total production 10.40% 7.50% 10.70% 7.90%
Manufacturer Three [Member]        
Concentration Risk [Line Items]        
Percentage of total production 8.90% 7.40% 9.60% 7.20%
Manufacturer Four [Member]        
Concentration Risk [Line Items]        
Percentage of total production 6.60% 6.90% 5.40% 5.70%
Manufacturer Five [Member]        
Concentration Risk [Line Items]        
Percentage of total production 5.00% 3.50% 4.20% 3.90%