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

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Note 7 - Stock-based Compensation and Other Plans (Details Textual) - USD ($)	3 Months Ended			6 Months Ended
	Jun. 30, 2020	Mar. 31, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019	May 31, 2019
Share-based Payment Arrangement, Option [Member]
Share-based Payment Arrangement, Expense	$ 70,000		$ 66,000	$ 95,000	$ 96,000
Share-based Payment Arrangement, Expense, Tax Benefit	11,000		17,000	17,000	24,000
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount, Total	202,000			202,000
Restricted Stock [Member]
Share-based Payment Arrangement, Expense	0		3,000	0	$ 5,000
Share-based Payment Arrangement, Expense, Tax Benefit	0		$ 1,000
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount, Total	$ 0			$ 0
The 2018 Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period (in shares)		585,000
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number, Ending Balance (in shares)		565,000
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant (in shares)						0
The 2008 Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period (in shares)		3,044,927