Consolidated Balance Sheets (Current Period Unaudited) (Parentheticals) - $ / shares shares in Thousands	Mar. 31, 2023	Dec. 31, 2022
Common stock, par value (in dollars per share)	$ 0.001	$ 0.001
Common stock, authorized (in shares)	200,000	200,000
Common stock, issued (in shares)	48,123	48,051
Common stock, outstanding (in shares)	48,109	48,037
Treasury Stock, Common, Shares	14	14