XML 75 R65.htm IDEA: XBRL DOCUMENT v3.10.0.1
Compensation Expense Associated with Performance Units (Detail) - Performance Units Awards - USD ($)
$ in Thousands
3 Months Ended 9 Months Ended
Sep. 30, 2018
Sep. 30, 2017
Sep. 30, 2018
Sep. 30, 2017
2018        
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]        
Stock-based compensation expense associated with Performance Units $ 667   $ 1,334  
2017        
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]        
Stock-based compensation expense associated with Performance Units 482 $ 482 1,445 $ 803
2016        
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]        
Stock-based compensation expense associated with Performance Units $ 321 321 963 963
2015        
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]        
Stock-based compensation expense associated with Performance Units   $ 338 $ 338 1,013
2014        
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]        
Stock-based compensation expense associated with Performance Units       $ 449