Income Taxes (Reconciliation of the Difference Between the Company's Effective Tax Rate and the U.S. Federal Statutory Tax Rate (as a percent)) (Details)	3 Months Ended	6 Months Ended
Apr. 30, 2020	Apr. 30, 2019	Apr. 30, 2020	Apr. 30, 2019
Reconciliation to the Company's effective income tax rate
Statutory U.S. federal income tax rate	21.00%	21.00%	21.00%	21.00%
State income tax, net of federal income tax benefits	8.80%	4.50%	5.90%	4.50%
Net (income) loss attributable to non-controlling and other beneficial interests	16.70%	(0.90%)	3.90%	(0.90%)
Stock-based and other compensation	1.50%	0.00%	0.70%	0.00%
Net excess tax benefits from stock-based compensation plans	(2.20%)	(0.20%)	(3.10%)	(1.20%)
Other items	(0.50%)	0.70%	0.10%	1.00%
Effective income tax rate	45.30%	25.10%	28.50%	24.40%

Effective Income Tax Rate Reconciliation, Other Items

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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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Percentage of domestic federal statutory tax rate applicable to pretax income (loss).

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Percentage 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 noncontrolling interest income (loss) exempt from income taxes.

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Percentage of difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying domestic federal statutory income tax rate to pretax income (loss) from continuing operation, attributable to nondeductible expense for share-based payment arrangement.

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Percentage of difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying domestic federal statutory income tax rate to pretax income (loss) from continuing operation, attributable to expense for award under share-based payment arrangement. Excludes expense determined to be nondeductible upon grant or after for award under share-based payment arrangement.

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Percentage 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 applicable to state and local income tax expense (benefit), net of federal tax expense (benefit).

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