Annual report pursuant to Section 13 and 15(d)

Equity - Summary of the Company's RSU Activity (Details)

v3.5.0.2
Equity - Summary of the Company's RSU Activity (Details) - Unvested restricted stock units - USD ($)
$ / shares in Units, $ in Millions
 12 Months Ended
Sep. 30, 2016
Sep. 30, 2015
Sep. 30, 2014
Summary of RSU activity      
Non-vested shares outstanding at the beginning of the period 861,540    
Granted (in shares) 481,901    
Vested (in shares) (480,873)    
Forfeited (in shares) (53,262)    
Non-vested shares outstanding at the end of the period 809,306 861,540  
Weighted-Average Grant-Date Fair value      
Non-vested shares outstanding at the beginning of the period (in dollars per share) $ 42.48    
Granted (in dollars per share) 52.00 $ 50.82 $ 46.49
Vested (in dollars per share) 43.08    
Forfeited (in dollars per share) 44.75    
Non-vested shares outstanding at the end of the period (in dollars per share) $ 47.64 $ 42.48  
Total fair value $ 27.1 $ 68.6 $ 38.7
Total unrecognized compensation cost related to unvested RSUs $ 38.5    
Unrecognized compensation cost period expected to be realized 4 years    
Weighted average remaining life (in years) 1 year 5 months