Condensed Consolidated Balance Sheets (Current Period Unaudited) (Parentheticals) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
Accounts receivable, allowance for doubtful accounts	$ 1,373	$ 3,393
Common stock, par value (in dollars per share)	$ 0.001	$ 0.001
Common stock, shares authorized (in shares)	50,000,000	50,000,000
Common stock, shares issued (in shares)	16,412,543	16,382,543
Common stock, shares outstanding (in shares)	16,412,543	16,382,543

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

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