Note 12 - Commitments and Contingencies (Details Textual) - USD ($)	9 Months Ended
May 31, 2019	Aug. 31, 2018	May 31, 2018
Accrued Bonuses	$ 1,450,000		$ 1,380,000
Entity Wide Trade Joint Venture Receivables, Three Joint Ventures,Percentage	76.40%	74.10%
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

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.

+ Details

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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=119400593&loc=d3e572229-122910

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.15(5))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

+ Details

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- Details

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- Details

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