v3.26.1
Stockholders' Equity (Summary of Activity in Common Stock and Treasury Stock Shares) (Details) - shares
 3 Months Ended 9 Months Ended
Jun. 30, 2026
Mar. 31, 2026
Jun. 30, 2025
Mar. 31, 2025
Jun. 30, 2026
Jun. 30, 2025
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]            
Balance, Common Stock, shares         72,960,000  
Balance, Treasury Stock, shares         (13,060,000)  
Balance, Treasury stock held for deferred compensation, shares         (28,000)  
Balance, Common Stock, shares 72,960,000       72,960,000  
Balance, Treasury Stock, shares (13,731,000)       (13,731,000)  
Balance, Treasury stock held for deferred compensation, shares (26,000)       (26,000)  
Common Stock [Member]            
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]            
Balance, Common Stock, shares 72,960,000   72,960,000   72,960,000 72,960,000
Balance, Common Stock, shares 72,960,000 72,960,000 72,960,000 72,960,000 72,960,000 72,960,000
Treasury Stock at Cost [Member]            
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]            
Balance, Treasury Stock, shares (13,367,000)   (13,380,000)   (13,060,000) (13,787,000)
Purchase of treasury stock, shares (520,000)   (231,000)   (1,606,000) (680,000)
Sales of treasury stock, shares 156,000   626,000   857,000 1,351,000
Common shares issued for benefit plans, shares 0 78,000 0 126,000 78,000 131,000
Balance, Treasury Stock, shares (13,731,000) (13,367,000) (12,985,000) (13,380,000) (13,731,000) (12,985,000)
Treasury Stock Held for Deferred Compensation [Member]            
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]            
Balance, Treasury stock held for deferred compensation, shares (27,000)   (30,000)   (28,000) (45,000)
Purchases of stock by deferred compensation, shares         (1,000) (1,000)
Distribution of stock from deferred compensation, shares 1,000   1,000   3,000 17,000
Balance, Treasury stock held for deferred compensation, shares (26,000) (27,000) (29,000) (30,000) (26,000) (29,000)