Net Income (Loss) Per Common Share - Calculations of Basic and Diluted Net Income Per Common Share (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended		9 Months Ended
	Jul. 31, 2021	Jul. 31, 2020	Jul. 31, 2021	Jul. 31, 2020
Schedule of Earnings Per Share, Basic and Diluted, by Common Class [Line Items]
(Loss) income from continuing operations	$ (13.7)	$ 56.0	$ 92.0	$ (52.9)
Income from discontinued operations, net of taxes	0.0	0.0	0.0	0.1
Net (loss) income	$ (13.7)	$ 56.0	$ 92.0	$ (52.8)
Weighted-average common and common equivalent shares outstanding — Basic (in shares)	67.5	66.9	67.3	66.9
Effect of dilutive securities
Weighted-average common and common equivalent shares outstanding — Diluted (in shares)	67.5	67.2	67.8	66.9
Net (loss) income per common share — Basic
(Loss) income from continuing operations (in USD per share)	$ (0.20)	$ 0.84	$ 1.37	$ (0.79)
Income from discontinued operations (in USD per share)	0	0	0	0
Net (loss) income (in USD per share)	(0.20)	0.84	1.37	(0.79)
Net (loss) income per common share — Diluted
(Loss) income from continuing operations (in USD per share)	(0.20)	0.83	1.36	(0.79)
Income from discontinued operations (in USD per share)	0	0	0	0
Net (loss) income (in USD per share)	$ (0.20)	$ 0.83	$ 1.36	$ (0.79)
Restricted stock units
Effect of dilutive securities
Effect of dilutive securities (in shares)	0.0	0.1	0.4	0.0
Stock options
Effect of dilutive securities
Effect of dilutive securities (in shares)	0.0	0.1	0.0	0.0
Performance shares
Effect of dilutive securities
Effect of dilutive securities (in shares)	0.0	0.1	0.1	0.0