Note 12 - Income Taxes - Income Tax Provision (Benefit) (Details)	12 Months Ended
Sep. 30, 2020	Sep. 30, 2019
Statutory federal rate	21.00%	(21.00%)
State income taxes, net of federal income tax expense (benefit)	5.60%	1.80%
Permanent differences for tax purposes	(2.80%)	9.20%
Change in rate	(1.00%)	9.70%
Write-off of deferred tax asset attributable to change in ownership (see below)		67.70%
Other	1.10%	(3.60%)
Effective Income Tax Rate Reconciliation, Percent, Total	23.90%	63.80%

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 permanent differences for tax purposes.

+ References

No definition available.

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

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
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-URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32687-109319

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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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