Note 8 - Stockholders' Equity - Stock Option and Warrant Activity (Details) - $ / shares	3 Months Ended
Dec. 31, 2022	Dec. 31, 2021
Granted, Options (in shares)	50,000	5,000
Restricted Stock [Member]
Outstanding (in shares)	200,000
Granted (in shares)	0
Exercised (in shares)	0
Forfeited (in shares)	0
Expired (in shares)	0
Outstanding, December 31, 2022 (in shares)	200,000
Share-Based Payment Arrangement, Option [Member]
Outstanding, Options (in shares)	1,157,927
Outstanding, Options, Weighted Average Exercise Price (in dollars per share)	$ 3.49
Granted, Options (in shares)	50,000
Granted, Options, Weighted Average Exercise Price (in dollars per share)	$ 1.34
Exercised, Options (in shares)	0
Exercised, Options, Weighted Average Exercise Price (in dollars per share)	$ 0
Forfeited, Options (in shares)	(15,833)
Forfeited, Options, Weighted Average Exercise Price (in dollars per share)	$ 2.51
Expired, Options (in shares)	0
Expired, Options, Weighted Average Exercise Price (in dollars per share)	$ 0
Outstanding, December 31, 2022 (in shares)	1,192,094
Outstanding, December 31, 2022 (in dollars per share)	$ 3.41
Options vested and exercisable, Options (in shares)	780,257
Options vested and exercisable, Weighted Average Exercise Price (in dollars per share)	$ 4.23
Stock Warrants [Member]
Outstanding (in shares)	1,757,629
Outstanding, Warrants, Weighted Average Exercise Price (in dollars per share)	$ 3.64
Granted (in shares)	0
Granted, Warrants, Weighted Average Exercise Price (in dollars per share)	$ 0
Exercised (in shares)	0
Exercised, Warrants, Weighted Average Exercise Price (in dollars per share)	$ 0
Forfeited (in shares)	0
Forfeited, Warrants, Weighted Average Exercise Price (in dollars per share)	$ 0
Expired (in shares)	0
Expired, Warrants, Weighted Average Exercise Price (in dollars per share)	$ 0
Outstanding, December 31, 2022 (in shares)	1,757,629
Outstanding, December 31, 2022 (in dollars per share)	$ 3.64

The element representing the weighted average exercise price of exercised stock warrants.

No definition available.

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- Definition

Represents the weighted average exercise price of expired stock warrants.

+ References

No definition available.

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- Definition

Represents the weighted average exercise price of forfeited stock warrants.

+ References

No definition available.

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- Definition

Granted stock warrants, weighted average exercise price

+ References

No definition available.

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- Definition

Exercise price per share or per unit of warrants or rights outstanding.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 3
-URI https://asc.fasb.org/extlink&oid=126973232&loc=d3e21475-112644

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- Definition

Number of non-option equity instruments exercised by participants.

+ References

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- Definition

Number of shares under non-option equity instrument agreements for which rights to exercise lapsed.

+ References

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- Definition

Number of shares under non-option equity instrument agreements that were cancelled as a result of occurrence of a terminating event.

+ References

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- Definition

Net number of non-option equity instruments granted to participants.

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- Definition

Number of equity instruments other than options outstanding, including both vested and non-vested instruments.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(ii)
-URI https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901

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-Section 50
-Paragraph 2
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-URI https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901

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- Definition

The weighted-average price as of the balance sheet date at which grantees can acquire the shares reserved for issuance on vested portions of options outstanding and currently exercisable under the stock option plan.

+ References

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- Definition

Number of options or other stock instruments for which the right to exercise has lapsed under the terms of the plan agreements.

+ References

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- Definition

The number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan.

+ References

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- Definition

Gross number of share options (or share units) granted during the period.

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- Definition

Number of options outstanding, including both vested and non-vested options.

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- Definition

Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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- Definition

Number of fully vested and expected to vest exercisable options that may be converted into shares under option plan. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

+ References

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- Definition

Weighted average price at which option holders acquired shares when converting their stock options into shares.

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- Definition

Weighted average price at which grantees could have acquired the underlying shares with respect to stock options of the plan that expired.

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- Definition

Weighted average price at which grantees could have acquired the underlying shares with respect to stock options that were terminated.

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- Definition

Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options.

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- Definition

Number of share options (or share units) exercised during the current period.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(iv)(02)
-URI https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(28))
-URI https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
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