Note 15 - Commitments and Contingencies (Details Textual) - USD ($)	12 Months Ended
Aug. 31, 2020	Aug. 31, 2019
Lessee, Operating Lease, Option to Extend Term One (Year)	5 years
Lessee, Operating Lease, Option to Extend Term Two (Year)	10 years
Finance and Operating Lease, Weighted Average Remaining Lease Term (Year)	2 years 7 days
Operating Lease, Weighted Average Discount Rate, Percent	2.31%
Operating Lease, Expense	$ 131,840
Accrued Bonuses	$ 1,300,000	$ 2,000,000
Entity Wide Trade Joint Venture Receivables, Three Joint Ventures, Percentage	88.20%	69.60%
Stock Options Granted to Management [Member]
Accrued Bonuses	$ 800,000	$ 800,000
Paid Out in Cash and Profit Sharing [Member]
Accrued Bonuses	$ 500,000	$ 1,200,000
Fiscal 2018 Bonus Plan [Member] \| Executive Officer [Member]
Percentage of Individual Bonus Payout Determined by Actual Versus Targeted EBITOI Results	75.00%
Percentage of Individuals Payout Determined Upon Achievement of Certain Pre-Established Individual Performance Objectives	25.00%

Percentage of total trade joint venture receivables accounted for by three joint ventures.

No definition available.

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- Definition

Weighted average remaining lease term for operating and finance lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

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- Definition

Represents option to extend term one for operating lease.

+ References

No definition available.

+ Details

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- Definition

Represents option to extend term two for operating lease.

+ References

No definition available.

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- Definition

Percentage of individual's bonus payout determined based upon the Company's actual EBITOI for the fiscal year compared to pre-established target EBITOI for the fiscal year.

+ References

No definition available.

+ Details

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- Definition

Percentage of individual's payout determined based upon achievement of certain pre-established individual performance objectives.

+ References

No definition available.

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- Definition

Carrying value as of the balance sheet date of obligations incurred and payable for incentive compensation awarded to employees and directors or earned by them based on the terms of one or more relevant arrangements.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03.15(a))
-URI http://asc.fasb.org/extlink&oid=120400017&loc=d3e572229-122910

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-Section S99
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-Subparagraph (SX 210.9-03.15(5))
-URI http://asc.fasb.org/extlink&oid=120398452&loc=d3e534808-122878

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- Definition

Amount of operating lease expense. Excludes sublease income.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 45
-Paragraph 4
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=121603541&loc=SL77918638-209977

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- Definition

Weighted average discount rate for operating lease calculated at point in time.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 50
-Paragraph 4
-Subparagraph (g)(4)
-URI http://asc.fasb.org/extlink&oid=121609121&loc=SL77918686-209980

Reference 2: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 55
-Paragraph 53
-URI http://asc.fasb.org/extlink&oid=121568110&loc=SL77918982-209971

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