Consolidated Balance Sheets (Parentheticals) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Condensed Consolidated Balance Sheet Parenthetical [Abstract]
Allowance for Doubtful Accounts Receivable, Current	$ 119	$ 170
Unamortized debt issuance costs	7	7
Unamortized debt issuance costs, noncurrent	$ 14	$ 21
Common stock, par value	$ 0	$ 0
Common stock, shares authorized	75,000,000	75,000,000
Common stock, shares issued	30,305,000	30,825,000
Common stock, shares outstanding	30,305,000	30,825,000