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Income Taxes - Changes to Deferred Tax Asset Valuation Allowance (Details) - USD ($) $ in Millions | 12 Months Ended
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Oct. 31, 2020 | Oct. 31, 2019 | Oct. 31, 2018
Operating Loss Carryforwards, Valuation Allowance Rollforward [Roll Forward] |  |  |
Valuation allowance at beginning of year | $ 8.4 | $ 12.0 | $ 7.7
GCA acquisition | 0.0 | 0.0 | 2.4
Other, net | (4.3) | (3.6) | 1.8
Valuation allowance at end of year | $ 4.1 | $ 8.4 | $ 12.0

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- Definition Operating Loss Carryforwards, Valuation Allowance Rollforward [Roll Forward] + References No definition available. + Details
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- Definition Operation Loss Carryforwards, Valuation Allowance, Business Acquisition + References No definition available. + Details
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- Definition Operation Loss Carryforwards, Valuation Allowance, Other + References No definition available. + Details
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- Definition The portion of the valuation allowance pertaining to the deferred tax asset representing potential future taxable deductions from net operating loss carryforwards for which it is more likely than not that a tax benefit will not be realized. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32537-109319 + Details
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