Annual report pursuant to Section 13 and 15(d)

Segment Information - Additional Information (Detail)

v3.8.0.1
Segment Information - Additional Information (Detail) - Sales Revenue, Net - Customer
12 Months Ended
Dec. 31, 2017
Dec. 31, 2016
Dec. 31, 2015
Customer Concentration Risk | United States      
Segment Reporting Information [Line Items]      
Concentration Risk Percentage 62.00% 64.00% 61.00%
Customer Concentration Risk | International      
Segment Reporting Information [Line Items]      
Concentration Risk Percentage 38.00% 36.00% 39.00%
Geographic Concentration Risk | International      
Segment Reporting Information [Line Items]      
Number of customers which represented more than 10% of the Company's revenue 0 0 0