Post Retirement Benefit Plans - Changes in Accumulated Other Comprehensive (Income) or Loss (Details) - USD ($) $ in Millions	12 Months Ended
Oct. 31, 2018	Oct. 31, 2017
Defined Benefit Plan, Changes in Accumulated Other Comprehensive (Income) Loss [Roll Forward]
Accumulated other comprehensive loss at beginning of year	$ 168.1	$ 199.8
Increase or (decrease) in accumulated other comprehensive (income) or loss
Net prior service costs amortized during fiscal year	0.2	0.1
Net loss amortized during fiscal year	(11.0)	(10.9)
Loss recognized during fiscal year due to settlement	(1.4)	(27.8)
Prior service credit occurring during fiscal year	3.3	(0.2)
Liability loss occurring during fiscal year	(39.2)	13.2
Asset gain occurring during fiscal year	34.6	(10.5)
Other adjustments	(2.7)	0.0
Increase (decrease) in accumulated other comprehensive loss	(16.2)	(36.1)
Foreign currency impact	(1.5)	4.4
Accumulated other comprehensive loss at fiscal year end	$ 150.4	$ 168.1

Defined Benefit Plan, Accumulated Other Comprehensive Income(Loss), Minimum Pension Liability, before Tax

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Defined Benefit Plan, Accumulated Other Comprehensive Income (Loss), Other Adjustments

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Defined Benefit Plan, Accumulated Other Comprehensive (Income) Loss, before Tax, Including Foreign Currency Impact

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Defined Benefit Plan, Changes in Accumulated Other Comprehensive (Income) Loss [Roll Forward]

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Other comprehensive income foreign currency impact.

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Amount, before tax, of accumulated other comprehensive (income) loss for defined benefit plan, that has not been recognized in net periodic benefit cost (credit).

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Amount, before tax, of cost (credit) of benefit change attributable to participants' prior service from plan amendment or plan initiation of defined benefit plan, that has not been recognized in net periodic benefit cost (credit).

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Amount, before tax, of reclassification adjustment from accumulated other comprehensive (income) loss for prior service cost (credit) of defined benefit plan.

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Amount, before tax, of increase (decrease) to other comprehensive income from settlement and curtailment gain (loss) of defined benefit plan.

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Amount, before tax, after reclassification adjustment, of (increase) decrease in accumulated other comprehensive income for defined benefit plan.

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Amount, before tax, of reclassification adjustment from accumulated other comprehensive income (loss) for gain (loss) of defined benefit plan.

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Amount, before tax, of reclassification adjustment from accumulated other comprehensive income (loss) for transition asset (obligation) of defined benefit plan.

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