Summary of Significant Accounting Policies (Narrative) (Details) gal in Millions	12 Months Ended
Oct. 31, 2021 USD ($) segment gal	Oct. 31, 2020 USD ($)
Product Information [Line Items]
Short term contract liabilities from contracts with customers \| $	$ 0	$ 0
Current accounts receivable term (days or less)	30 days
Impairment of long-lived assets \| $	$ 0	$ 0
Number of reportable business segments \| segment	1
Renewable Fuels Marketing Group (RPMG)
Product Information [Line Items]
Equity method investment ownership percentage	5.55%
Lawrenceville Tank, LLC
Product Information [Line Items]
Equity method investment ownership percentage	7.00%
Ethanol Contracts
Product Information [Line Items]
Annual production capacity \| gal	50.0
Denatured Ethanol
Product Information [Line Items]
Annual production capacity \| gal	70.2

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