Annual report pursuant to Section 13 and 15(d)

Segment and Geographic Information - Company's Top Five Manufacturers Produced (Detail)

v3.20.4
Segment and Geographic Information - Company's Top Five Manufacturers Produced (Detail) - Cost of Goods, Total [Member] - Supplier Concentration Risk [Member]
12 Months Ended
Dec. 31, 2020
Dec. 31, 2019
Dec. 31, 2018
Segment Reporting Information [Line Items]      
Percentage of Total Production 42.10% 40.60% 41.90%
Manufacturer One [Member]      
Segment Reporting Information [Line Items]      
Percentage of Total Production 21.00% 16.00% 12.80%
Manufacturer Two [Member]      
Segment Reporting Information [Line Items]      
Percentage of Total Production 6.20% 7.30% 10.10%
Manufacturer Three [Member]      
Segment Reporting Information [Line Items]      
Percentage of Total Production 5.80% 7.20% 8.60%
Manufacturer Four [Member]      
Segment Reporting Information [Line Items]      
Percentage of Total Production 4.90% 5.10% 5.40%
Manufacturer Five [Member]      
Segment Reporting Information [Line Items]      
Percentage of Total Production 4.20% 5.00% 5.00%