XML 56 R46.htm IDEA: XBRL DOCUMENT v3.10.0.1
Restricted Stock Units - Narrative (Details) - USD ($)
shares in Thousands, $ in Thousands
3 Months Ended 6 Months Ended
Jun. 30, 2018
Jun. 30, 2018
Dec. 31, 2017
Vested deferred restricted stock units      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Vested and remaining outstanding (in shares) 988 988  
Unvested units outstanding (in shares) 2,393 2,393 1,752
Unrecognized stock-based compensation expense $ 611 $ 611  
Vested deferred restricted stock units | Non-Employee Directors      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Vested and remaining outstanding (in shares)   988  
Performance-based Restricted Stock Units      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Unvested units outstanding (in shares) 1,528 1,528  
Unrecognized stock-based compensation expense $ 457 $ 457  
Time-based Restricted Stock Units      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Unvested units outstanding (in shares) 865 865  
Unrecognized stock-based compensation expense $ 154 $ 154  
Weighted average period for amortization of unrecognized stock-based compensation   1 month 10 days