Income Taxes (Narrative) (Details) - USD ($) $ in Millions	3 Months Ended
Jan. 31, 2019	Jan. 31, 2018	Oct. 31, 2018
Components of Income Tax Expense (Benefit), Continuing Operations [Abstract]
Income tax expense (benefit) to finalize tax effects of 2017 Act	$ (4.4)
Effective income tax rate	10.00%	263.70%
Change of provisional tax expenses related to 2017 Act		$ 202.0
Discrete tax benefits	$ 18.7
Unrecognized tax benefits	47.1		$ 68.9
Unrecognized tax benefits that could be settled	$ 3.1

Effective Income Tax Rate Reconciliation, Tax Cuts And Jobs Act, Amount

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Tax Cuts And Jobs Act, Income Tax Expense (Benefit)

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Amount of decrease reasonably possible in the next twelve months for the unrecognized tax benefit.

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

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Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to tax exempt income, equity in earnings (loss) of an unconsolidated subsidiary, minority noncontrolling interest income (loss), tax holiday, disposition of a business, disposition of an asset, repatriation of foreign earnings, repatriation of foreign earnings jobs creation act of 2004, increase (decrease) in enacted tax rate, prior year income taxes, increase (decrease) in deferred tax asset valuation allowance, and other adjustments.

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Amount of unrecognized tax benefits.

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