Quarterly report pursuant to Section 13 or 15(d)

Stock-Based Compensation (Details)

v3.8.0.1
Stock-Based Compensation (Details)
shares in Thousands
3 Months Ended
Mar. 31, 2018
$ / shares
shares
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward]  
Nonvested Beginning balance Number of shares | shares 88
Granted, Number of shares | shares 101
Vested, Number of shares | shares (24)
Forfeitures, Number of shares | shares (5)
Nonvested Ending balance Number of shares | shares 160
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Roll Forward]  
Nonvested Beginning balance, Weighted average grant-date fair value | $ / shares $ 34.44
Granted, Weighted average grant-date fair value | $ / shares 53.81
Vested, Weighted average grant-date fair value | $ / shares 35.45
Forfeitures, Weighted average grant-date fair value | $ / shares 35.00
Nonvested Ending balance, Weighted average grant-date fair value | $ / shares $ 46.51