Annual report pursuant to Section 13 and 15(d)

Share-Based Compensation (Details)

v3.22.2.2
Share-Based Compensation (Details) - USD ($)
$ / shares in Units, $ in Millions
12 Months Ended
Sep. 30, 2022
Sep. 30, 2021
Sep. 30, 2020
Compensation Related Costs [Abstract]      
Number of shares initially registered and authorized for issuance 15,385,436    
Total number of shares outstanding (in shares) 2,779,027    
Number of shares issued (in shares) 8,946,245    
Number of shares available for future issuance (in shares) 3,660,164    
Stock-based compensation cost $ 21.3 $ 19.7 $ 14.0
Less impact of income tax 4.9 4.5 3.2
Stock-based compensation cost, net of tax 16.4 15.2 10.8
Current tax benefit realized from the exercise of stock options and payment of restricted stock units $ 5.8 $ 3.9 $ 1.9
Time Based Stock Awards      
Assumptions used in the determination of fair value of options      
Expected life 2 years 9 months 29 days 2 years 9 months 29 days 2 years 9 months 25 days
Risk-free interest rate (as a percent) 0.86% 0.20% 1.60%
Weighted-average dividend yield (as a percent) 0.00% 0.00% 0.00%
Actual dividend rate (as a percent) 1.91% 2.24% 2.63%
Weighted-average volatility factor (as a percent) 43.90% 43.04% 25.61%
Weighted average exercise price      
Unrecognized stock-based compensation $ 16.0    
Period for recognition of unrecognized stock-based compensation 2 years 3 months 18 days    
Number of shares      
Number of shares outstanding under time-based stock awards and performance-based stock awards at the beginning of the period (in shares) 617,135 346,625  
Granted (in shares) 408,467 454,873  
Vested (in shares) (252,346) (117,370)  
Forfeited (in shares) (112,796) (66,993)  
Number of shares outstanding under time-based stock awards and performance-based stock awards at the end of the period (in shares) 660,460 617,135 346,625
Weighted-Average Grant Date Fair Value      
Non-vested time-based stock awards at the beginning of the period (in dollars per share) $ 37.21 $ 32.46  
Granted (in dollars per share) 45.46 39.37  
Vested (in dollars per share) 35.36 32.95  
Forfeited (in dollars per share) 40.28 34.72  
Non-vested time-based stock awards at the end of the period (in dollars per share) $ 42.50 $ 37.21 $ 32.46
Aggregate fair value $ 24.3    
Time Based Stock Awards and Performance Based Stock Awards      
Time-based stock awards and performance-based stock awards      
Total vest date fair value of vested time-based stock awards and performance-based stock awards shares held by employees and directors $ 23.0 $ 11.1 $ 5.5
Weighted-Average Grant Date Fair Value      
Number of shares under the time-based and performance-based stock awards due to dividend reinvestment (in shares) 40,729    
Aggregate fair value of shares under the time-based and performance-based stock awards plans due to dividend reinvestment $ 1.5    
Vested Deferred Stock      
Vested deferred stock (in shares) 328,494    
Aggregate fair value of vested deferred stock $ 12.1    
Employee Stock Option      
Share-based compensation      
Vesting period 3 years 3 years  
Weighted average fair value of options granted (in dollars per share)     $ 6.63
Assumptions used in the determination of fair value of options      
Expected life   5 years 9 months 18 days  
Risk-free interest rate (as a percent)   1.60%  
Weighted-average dividend yield (as a percent)   2.70%  
Weighted-average volatility factor (as a percent)   27.90%  
Number of shares      
Outstanding at the beginning of the period (in shares) 1,962,950 2,436,443  
Granted (in shares) 0 0  
Exercised (in shares) (702,712) (453,059)  
Forfeited (in shares) (544) (9,783)  
Expired (in shares) (7,972) (10,651)  
Outstanding at the end of the period (in shares) 1,251,722 1,962,950 2,436,443
Exercisable at the end of the period (in shares) 1,184,283    
Weighted average exercise price      
Outstanding at the beginning of the period (in dollars per share) $ 36.35 $ 35.00  
Granted (in dollars per share) 0 0  
Exercised (in dollars per share) 36.13 28.86  
Forfeited (in dollars per share) 44.22 41.52  
Expired (in dollars per share) 35.91 41.74  
Outstanding at the end of the period (in dollars per share) 36.47 $ 36.35 $ 35.00
Exercisable at the end of the period (in dollars per share) $ 36.73    
Average remaining life of outstanding stock options 4 years 1 month 6 days    
Aggregate intrinsic value of outstanding options $ 3.8    
Average remaining life of the exercisable options 3 years 10 months 24 days    
Aggregate intrinsic value of exercisable options $ 3.4    
Total intrinsic value of options exercised 9.6 $ 6.6 $ 0.6
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested, Number of Shares $ 11.5 $ 15.9 $ 15.6
Employee Stock Option | Maximum      
Share-based compensation      
Award expiration term 10 years    
Performance Shares      
Weighted average exercise price      
Unrecognized stock-based compensation $ 6.9    
Period for recognition of unrecognized stock-based compensation 1 year 9 months 18 days    
Number of shares      
Number of shares outstanding under time-based stock awards and performance-based stock awards at the beginning of the period (in shares) 733,649 694,295  
Granted (in shares) 321,472 369,138  
Vested (in shares) (242,117) (135,569)  
Forfeited (in shares) (274,652) (194,215)  
Number of shares outstanding under time-based stock awards and performance-based stock awards at the end of the period (in shares) 538,352 733,649 694,295
Weighted-Average Grant Date Fair Value      
Non-vested time-based stock awards at the beginning of the period (in dollars per share) $ 37.38 $ 36.59  
Granted (in dollars per share) 51.93 44.36  
Vested (in dollars per share) 33.65 38.35  
Forfeited (in dollars per share) 39.22 46.88  
Non-vested time-based stock awards at the end of the period (in dollars per share) $ 47.69 $ 37.38 $ 36.59
Aggregate fair value $ 18.5    
Vested Deferred Stock      
Performance measurement period used to determined shares granted included in performance-based stock awards 3 years    
Performance Shares, SV      
Share-based compensation      
Vesting period 3 years    
Performance Shares, TSR      
Share-based compensation      
Vesting period 3 years    
Vested Deferred Stock      
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Below 25th Percentile, Payout Percent 0.00%    
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, At 25th Percentile, Payout Percent 25.00%    
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, At 50th Percentile, Payout Percent 100.00%    
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, At 75th Percentile And Above, Payout Percent 175.00%