v3.26.1
Earnings (loss) per common share (Details) - USD ($)
$ / shares in Units, shares in Millions, $ in Millions
 3 Months Ended 6 Months Ended
Jun. 30, 2026
Mar. 31, 2026
Jun. 30, 2025
Mar. 31, 2025
Jun. 30, 2026
Jun. 30, 2025
Numerator:            
Net income (loss) $ (180.2) $ 6.8 $ (12.0) $ 68.0 $ (173.4) $ 56.0
Denominator:            
Weighted-average number of shares outstanding-basic (in shares) 51.6   54.2   51.7 54.3
Dilutive securities - equity awards (in shares) 0.0   0.0   0.0 2.4
Weighted-average number of shares outstanding-diluted (in shares) 51.6   54.2   51.7 56.7
Earnings (loss) per common share - basic (in dollars per share) $ (3.49)   $ (0.22)   $ (3.35) $ 1.03
Earnings (loss) per common share - diluted (in dollars per share) $ (3.49)   $ (0.22)   $ (3.35) $ 0.99
Anti-dilutive securities (in shares) 6.9   7.1   5.3 4.6