v3.26.1
Stockholders' Equity - Share Repurchase Program (Details) - 2017 Share Repurchase program - USD ($)
shares in Millions
 3 Months Ended 9 Months Ended
Jun. 30, 2026
Jun. 30, 2025
Jun. 30, 2026
Jun. 30, 2025
Aug. 31, 2017
Equity, Class of Treasury Stock [Line Items]          
Amount of shares authorized to be repurchased         $ 1,000,000,000.0
Remaining authorization $ 395,900,000   $ 395,900,000    
Number of shares repurchased (in shares) 1.9 1.5 4.9 3.3  
Total cost of share repurchased $ 25,300,000 $ 13,000,000.0 $ 71,400,000 $ 33,000,000.0