Income Taxes - Narrative (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Apr. 30, 2020	Apr. 30, 2019	Apr. 30, 2020	Apr. 30, 2019
Income Tax Disclosure [Abstract]
Effective income tax rate (percent)	(8.40%)	29.60%	(21.40%)	28.70%
Income tax provision	$ (10.6)	$ (12.6)	$ (19.2)	$ (17.3)
Increase (decrease) in tax credits, work opportunity tax credit		$ 1.3	$ 1.5	1.4
Unrecognized tax benefits, increase resulting from current period tax positions				$ 1.4

Increase (Decrease) in Tax Credits, Work Opportunity Tax Credit

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- Definition

Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

+ References

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-Publisher FASB
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- References

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Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
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Amount of increase in unrecognized tax benefits resulting from tax positions that have been or will be taken in current period tax return.

+ References

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