XML 102 R84.htm IDEA: XBRL DOCUMENT v3.10.0.1
Stock-based Compensation Plans (Schedule of Share-based Compensation. Option Activity (Details) - USD ($)
$ / shares in Units, $ in Millions
12 Months Ended
Sep. 30, 2018
Sep. 30, 2017
Sep. 30, 2016
Sep. 30, 2015
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Outstanding, shares 2,440,654 3,554,308 3,992,666  
Outstanding, Weighted average exercise price (per share) $ 5.03 $ 5.72 $ 5.99 $ 6.54
Outstanding, Weighted average remaining contractual term, years 1 year 10 months 24 days 2 years 6 months 3 years 4 months 24 days 4 years 2 months 12 days
Outstanding, Aggregate intrinsic value $ 10.3 $ 17.3 $ 23.8 $ 9.3
Exercised, shares (851,628) (905,834) (270,599)  
Exercised, Weighted average exercise price (per share) $ 7.00 $ 4.71 $ 6.83  
Exercised, Aggregate intrinsic value $ 3.8 $ 7.3 $ 0.8  
Canceled, shares 0 (207,820) (167,759)  
Canceled, Weighted average exercise price (per share) $ 0 $ 14.72 $ 17.82  
Stock Options, Exercisable, Number 1,589,026      
Exercisable, Weighted average exercise price (per share) $ 5.03      
Exercisable, Weighted average remaining contractual term, years 1 year 10 months 24 days      
Exercisable, Aggregate intrinsic value $ 10.3      
Outstanding, shares 1,589,026 2,440,654 3,554,308 3,992,666