Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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

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The number of equity-based payment instruments, excluding stock (or unit) options, that were forfeited during the reporting period.

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Note 7 - Stock-based Compensation (Details Textual) - USD ($)		3 Months Ended			9 Months Ended		12 Months Ended
	Jan. 04, 2017	Sep. 30, 2021	Sep. 30, 2020	Mar. 31, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2019	Jun. 30, 2021
Incentive Compensation Plan [Member]
Common Stock, Capital Shares Reserved for Future Issuance (in shares)								2,580,000
Share-based Payment Arrangement, Expense		$ 109,000	$ 80,000		$ 312,000	$ 189,000
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount, Total		$ 11,000			$ 11,000
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition (Year)					4 years
Performance Share Award Agreement [Member] \| Performance Shares [Member]
Share-based Payment Arrangement, Expense							$ 108,000
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount, Total				$ 434,000
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period (in shares)	161,766
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeited in Period (in shares)				129,000