Annual report pursuant to Section 13 and 15(d)

Share-based Compensation - Schedule of Share-Based Compensation Expense Based on Fair Value of Options (Detail)

v3.6.0.2
Share-based Compensation - Schedule of Share-Based Compensation Expense Based on Fair Value of Options (Detail) - Stock Options [Member] - $ / shares
12 Months Ended
Dec. 31, 2016
Dec. 31, 2015
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Expected volatility 35.00%  
Risk free interest rate 0.69%  
Expected lives at date of grant (in years) 5 years 4 days 4 years 5 months 5 days
Weighted average fair value of options granted $ 2.76 $ 2.90
Minimum [Member]    
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Expected volatility   50.00%
Risk free interest rate   0.25%
Maximum [Member]    
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Expected volatility   54.00%
Risk free interest rate   0.66%