XML 52 R41.htm IDEA: XBRL DOCUMENT v3.20.2
Stockholders' Equity (Details) - USD ($)
$ / shares in Units, $ in Millions
3 Months Ended 9 Months Ended
Jun. 30, 2020
Jun. 30, 2019
Jun. 30, 2020
Jun. 30, 2019
Sep. 30, 2018
Class of Stock [Line Items]          
Equity Securities Registered, Value         $ 500.0
Common Stock Available for Issuance, Value Remaining $ 394.3   $ 394.3    
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period     175,325    
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value     $ 16.01    
Stock-based compensation expense $ 0.3 $ 0.9 $ 1.6 $ 1.1  
Retirement Eligible [Member]          
Class of Stock [Line Items]          
Stock-based compensation expense   $ 0.6 $ 0.5 $ 0.6