v3.26.1
(Loss) Earnings per Share - Calculation of (Loss) Earnings per Basic and Diluted Common Share (Details) - USD ($)
$ / shares in Units, shares in Thousands, $ in Millions
 3 Months Ended 6 Months Ended
Mar. 31, 2026
Mar. 31, 2025
Mar. 31, 2026
Mar. 31, 2025
Earnings Per Share [Abstract]        
Net (Loss) Income $ (4.1) $ 23.5 $ 40.0 $ 23.5
Basic weighted average number of shares outstanding (in shares) 59,299 58,290 59,044 58,119
Stock awards and equity units (share equivalent) (in shares) 0 257 682 537
Diluted weighted average shares outstanding (in shares) 59,299 58,547 59,726 58,656
(Loss) Earnings per common share - Basic (in dollars per share) $ (0.07) $ 0.40 $ 0.68 $ 0.40
(Loss) Earnings per common share - Diluted (in dollars per share) $ (0.07) $ 0.40 $ 0.67 $ 0.40
Antidilutive Shares (millions) (in shares) 4,100 3,900 1,800 2,500