Quarterly report pursuant to Section 13 or 15(d)

Share-Based Payments - Non-employee Director Non-vested Shares (Details)

v3.19.1
Share-Based Payments - Non-employee Director Non-vested Shares (Details) - USD ($)
$ / shares in Units, shares in Thousands, $ in Thousands
 3 Months Ended
Mar. 31, 2019
Mar. 31, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Share-based compensation expense $ 3,047 $ 2,261
Nonemployee Director Nonvested Shares Granted Member    
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Non-Employee Director Shares, Vesting Period (in years) 1 year  
Outstanding and non-vested, beginning of period (in shares) 15  
Outstanding and non-vested, end of period (in shares) 15  
Outstanding and non-vested, weighted-average grant date fair value, beginning of period $ 59  
Outstanding and non-vested, weighted-average grant date fair value, end of period $ 59  
Outstanding and non-vested, aggregate grant date fair value $ 886  
Share-based compensation expense 218 185
Tax benefit related to share-based expense 52 47
Unrecognized share-based compensation, net of estimated forfeitures $ 142 $ 65
Weighted average period over which unrecognized compensation will be recognized (years) 2 months 11 days