Condensed Consolidated Balance Sheets (Current Period Unaudited) (Parentheticals) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Accounts receivable allowance	$ 493	$ 335	[1]
Preferred stock, par value (in dollars per share)	$ 1	$ 1	[1]
Preferred stock, shares authorized (in shares)	1,000,000	1,000,000	[1]
Preferred stock, shares issued (in shares)	250,000	250,000	[1]
Preferred stock, shares outstanding (in shares)	250,000	250,000	[1]
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, shares authorized (in shares)	9,000,000	9,000,000
Common stock, shares issued (in shares)	2,657,530	2,657,530
Common stock, shares outstanding (in shares)	2,657,530	2,657,530

[1] The balance sheet at December 31, 2019 has been derived from the audited financial statements at that date