Income Taxes - Narrative (Details) - USD ($) $ in Millions	3 Months Ended
	Jan. 31, 2021	Jan. 31, 2020
Income Tax Disclosure [Abstract]
Effective income tax rate (percent)	26.70%	23.60%
Income tax provision	$ (27.2)	$ (8.6)
Social security tax, employer, deferral, CARES Act	$ 132.0