Condensed Consolidated Balance Sheets (Unaudited) (Parentheticals) - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019
Statement of Financial Position [Abstract]
Allowance for doubtful trade receivables	$ 62	$ 45
Unamortized debt issuance costs, current	70	0
Unamortized debt issuance costs, long-term	$ 270	$ 230
Common stock, par value (in dollars per share)	$ 0	$ 0
Common stock, shares authorized	75,000,000	75,000,000
Common stock, shares issued	29,967,000	29,781,000
Common stock, shares outstanding	29,967,000	29,781,000

Amount of allowance for credit loss on accounts receivable, classified as current.

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