Condensed Consolidated Balance Sheets (Current Period Unaudited) (Parentheticals) - USD ($) $ in Thousands	Mar. 31, 2023	Dec. 31, 2022
Accumulated depreciation	$ 18,646	$ 18,557
Accumulated amortization, intangible assets	$ 418	$ 406
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, shares authorized (in shares)	40,000,000	40,000,000
Common stock, shares issued (in shares)	31,272,303	31,272,303
Common stock, shares outstanding (in shares)	30,296,297	30,296,297