Condensed Consolidated Balance Sheets (Unaudited) (Parentheticals) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Statement of Financial Position [Abstract]
Allowance for doubtful trade receivables	$ 28	$ 99
Unamortized debt issuance costs, current	0	7
Unamortized debt issuance costs, long-term	$ 80	$ 7
Common stock, par value (in dollars per share)	$ 0	$ 0
Common stock, shares authorized	75,000,000	75,000,000
Common stock, shares issued	29,593,000	29,545,000
Common stock, shares outstanding	29,593,000	29,545,000

A valuation allowance for trade and other receivables due to an Entity within one year (or the normal operating cycle, whichever is longer) that are expected to be uncollectible.

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