Quarterly report pursuant to Section 13 or 15(d)

Summary of Significant Accounting Policies - Stock-Based Compensation Expense (Details)

v3.10.0.1
Summary of Significant Accounting Policies - Stock-Based Compensation Expense (Details) - USD ($)
$ in Thousands
3 Months Ended 9 Months Ended
Sep. 30, 2018
Sep. 30, 2017
Sep. 30, 2018
Sep. 30, 2017
Jan. 01, 2018
Dec. 31, 2017
Jan. 01, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]              
Deferred income tax assets, net         $ 1,003    
Stock-based compensation expense $ 390 $ 326 $ 1,137 $ 976      
Stock Options              
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]              
Non-vested stock options unrecognized compensation expense $ 3,119   $ 3,119        
Non-vested stock options unrecognized compensation expense, weighted-average period of recognition     2 years 2 months 12 days        
Accounting Standards Update 2016-09              
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]              
Deferred income tax assets, net             $ 4,000
Accounting Standards Update 2016-09 | Retained Earnings              
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]              
Credit to retained earnings           $ (4,000)