Employee Benefits - Changes in Benefit Obligation, Changes in Plan Assets and Funded Status (Details) - USD ($) $ in Millions	12 Months Ended
	Oct. 31, 2023	Oct. 31, 2022	Oct. 31, 2021
Change in benefit obligation
Benefit obligation, beginning of year	$ 148.0	$ 230.9	$ 218.8
Service cost	10.0	18.3	17.2
Interest cost	7.9	5.1	4.4
Benefits paid	(10.5)	(13.1)	(11.5)
Actuarial (gain)/loss	(10.9)	(93.2)	2.0
Benefit obligation, end of year	$ 144.5	$ 148.0	$ 230.9
Defined Benefit Plan, Net Periodic Benefit Cost (Credit), Interest Cost, Statement of Income or Comprehensive Income [Extensible Enumeration]	Other liabilities	Other liabilities	Other liabilities
Change in plan assets
Fair value of plan assets, beginning of year	$ 142.9	$ 199.5	$ 159.5
Actual return on plan assets	4.1	(43.5)	38.8
Employer contributions	1.1	0.0	12.7
Benefits paid	(10.5)	(13.1)	(11.5)
Fair value of plan assets, end of year	137.6	142.9	199.5
Funded status at end of year	$ (6.9)	$ (5.1)	$ (31.4)