Quarterly report pursuant to Section 13 or 15(d)

Stock-Based Compensation Plans - Stock-Based Compensation Expense (Detail)

v3.4.0.3
Stock-Based Compensation Plans - Stock-Based Compensation Expense (Detail) - USD ($)
$ in Thousands
3 Months Ended
Mar. 31, 2016
Mar. 31, 2015
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Share-based compensation expense - Independent contractors $ 530 $ 1,259
Allocated share-based compensation expense 1,325 1,907
Employee Stock Purchase Plan [Member]    
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Allocated share-based compensation expense 48 62
Restricted Stock Awards [Member] | Non-Employee Directors [Member]    
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Allocated share-based compensation expense 89 59
Restricted Stock Units (RSUs) [Member] | Employees [Member]    
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Allocated share-based compensation expense $ 658 $ 527