Quarterly report pursuant to Section 13 or 15(d)

Common Stock - Additional Information 1 (Detail)

v3.7.0.1
Common Stock - Additional Information 1 (Detail) - USD ($)
$ in Millions
3 Months Ended 6 Months Ended
Jun. 30, 2017
Jun. 30, 2016
Jun. 30, 2017
Jun. 30, 2016
Dec. 31, 2016
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]          
Unrecognized compensation expense related to stock options granted $ 0.3   $ 0.3   $ 0.6
Stock Options [Member]          
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]          
Weighted-average period, restricted stock awards     1 year    
Restricted Stock Unit [Member]          
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]          
Weighted-average period, restricted stock awards     1 year    
Award vesting period     4 years    
Stock based compensation expense 0.1 $ 0.4 $ 0.1 $ 0.6  
Total unrecognized compensation expense related to the Company's restricted stock unit awards $ 0.6   $ 0.6