Quarterly report pursuant to Section 13 or 15(d)

Stockholders' Equity - Employee Stock Purchase Programs (Detail)

v3.8.0.1
Stockholders' Equity - Employee Stock Purchase Programs (Detail) - USD ($)
$ in Thousands
 3 Months Ended
Mar. 31, 2018
Mar. 31, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Stock-based compensation expense $ 5,053 $ 2,929
Avenue [Member]    
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Stock-based compensation expense 349 5
Checkpoint [Member]    
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Stock-based compensation expense 1,137 979
Mustang [Member]    
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Stock-based compensation expense 1,995 0
Other [Member]    
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Stock-based compensation expense 112 115
Employee Awards [Member]    
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Stock-based compensation expense 828 367
Executive Awards [Member]    
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Stock-based compensation expense $ 632 $ 1,463