Quarterly report pursuant to Section 13 or 15(d)

Stock-Based Compensation (Narrative) (Details)

v3.8.0.1
Stock-Based Compensation (Narrative) (Details) - USD ($)
$ in Millions
3 Months Ended
Mar. 31, 2018
Mar. 31, 2017
Share-based Compensation [Abstract]    
Stock-based compensation cost $ 2.7 $ 2.6
Capitalized stock-based compensation cost 1.1 $ 1.0
Unrecognized compensation expense $ 12.9  
Weighted average period of expense recognition period 1 year 6 months 11 days