Consolidated Balance Sheets (Current Period Unaudited) (Parentheticals) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Statement of Financial Position [Abstract]
Allowance for doubtful accounts	$ 1,283	$ 637
Common stock, par value (in dollars per share)	$ 0.001	$ 0.001
Common stock, authorized (in shares)	200,000,000	200,000,000
Common stock, issued (in shares)	31,725,314	30,583,311
Common stock, outstanding (in shares)	31,725,314	30,583,311

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

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Face amount or stated value per share of common stock.

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