Note 9 - Stock Compensation Plans (Details Textual) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Share-based Payment Arrangement, Expense	$ 0.3	$ 0.3	$ 0.8	$ 0.9
Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Aggregate Intrinsic Value, Outstanding	$ 0.9		$ 0.9
Share Price (in dollars per share)	$ 2.96		$ 2.96
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant (in shares)	1,448,416		1,448,416

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

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Price of a single share of a number of saleable stocks of a company.

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Intrinsic value of outstanding award under share-based payment arrangement. Excludes share and unit options.

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