v3.26.1
Stock Compensation Plans: Disclosure of Share-based Compensation Arrangements by Share-based Payment Award (Details) - $ / shares
9 Months Ended
Jun. 30, 2026
Jun. 30, 2025
Shares:    
Options outstanding, beginning of period (shares) 215,530 306,240
Exercised (shares) (61,680) (41,960)
Forfeited (shares) (1,800) (11,300)
Options outstanding, end of period (shares) 152,050 252,980
Weighted Average Exercise Price (in dollars per share):    
Options outstanding, beginning of period (dollars per share) $ 26.22 $ 25.21
Exercised (dollars per share) 25.84 19.47
Forfeited (dollars per share) 27.68 28.41
Options outstanding, end of period (dollars per share) $ 26.35 $ 26.02