Additional percentage of vesting of award under share-based payment arrangement.

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Lower range limit of percentage of vesting of award under share-based payment arrangement.

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No definition available.

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Upper range limit of percentage of vesting of award under share-based payment arrangement.

+ References

No definition available.

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- Definition

The value of grants in period of equity instruments other than options under share based compensation arrangement.

+ References

No definition available.

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- Definition

Represents numbers of shares issued as a percentage under share-based compensation arrangement.

+ References

No definition available.

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- Definition

Amount of cost capitalized for award under share-based payment arrangement.

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Amount of cost not yet recognized for nonvested award under share-based payment arrangement.

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Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

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- Definition

The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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- Definition

Fair value of share-based awards for which the grantee gained the right by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash.

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- Definition

Number of shares authorized for issuance under share-based payment arrangement.

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The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

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- Definition

Percentage of vesting of award under share-based payment arrangement.

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- Definition

Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Number of shares issued during the period related to Restricted Stock Awards, net of any shares forfeited.

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Note 10 - Stock-based Compensation Plan (Details Textual) - USD ($)			1 Months Ended	3 Months Ended			9 Months Ended
	Aug. 24, 2023	Mar. 08, 2023	Aug. 31, 2020	Sep. 30, 2023	Sep. 30, 2022	Jun. 30, 2022	Sep. 30, 2023	Sep. 30, 2022	Jun. 21, 2023
Share-based Payment Arrangement, Amount Capitalized				$ 0	$ 0		$ 0	$ 0
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value (in dollars per share)							$ 9.43	$ 4.53
Share-Based Payment Arrangement, Option [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Expiration Period (Year)							10 years
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period (Year)							4 years
Restricted Stock [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Grants in Period (in shares)							97,461
Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Vested in Period, Fair Value							$ 1,688,000	$ 550,000
Restricted Stock [Member] \| Employees [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period (Year)							4 years
Restricted Stock [Member] \| Independent Directors [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period (Year)							1 year
Restricted Stock [Member] \| Independent Directors [Member] \| Share-Based Payment Arrangement, Tranche One [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage							25.00%
Restricted Stock [Member] \| Chief Executive Officer and Chief Financial Officer [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage		100.00%					100.00%
Share-based Compensation Arrangement By Share-based Payment Award, Award Vesting Rights Percentage Lower Range		0.00%
Share-based Compensation Arrangement By Share-based Payment Award, Award Vesting Rights Percentage Upper Range		150.00%
Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Grants in Period (in shares)		18,888
Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Grants in Period, Value		$ 303,000
Restricted Stock [Member] \| President of Environmental Technologies [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period (Year)		3 years
Share-based Compensation Arrangement By Share-based Payment Award, Award Vesting Rights Percentage Lower Range		0.00%
Share-based Compensation Arrangement By Share-based Payment Award, Award Vesting Rights Percentage Upper Range		150.00%
Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Grants in Period (in shares)		5,081
Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Grants in Period, Value		$ 108,000
The 2023 Stock Incentive Plan [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Number of Shares Authorized (in shares)									350,000
Share-Based Compensation Arrangement by Share-Based Payment Award, Number of Shares Available for Grant (in shares)									1,117,942
Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount				$ 3,450			$ 3,450
Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition (Year)							2 years 2 months 12 days
Restricted Stock Vesting in Three Years [Member] \| Restricted Stock [Member]
Stock Issued During Period, Shares, Restricted Stock Award, Net of Forfeitures (in shares)	40,557
Share-Based Compensation Arrangement by Share-Based Payment Award, Shares Issued, Percentage	100.00%
Share-Based Compensation Arrangement by Share-Based Payment Award, Additional Award Vesting Rights, Percentage	50.00%
Restricted Stock Vesting in Three Years [Member] \| Restricted Stock [Member] \| Vesting Based On Performance Metrics [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage	150.00%		100.00%			150.00%
Share-based Compensation Arrangement By Share-based Payment Award, Award Vesting Rights Percentage Lower Range			0.00%
Share-based Compensation Arrangement By Share-based Payment Award, Award Vesting Rights Percentage Upper Range			150.00%