Consolidated Balance Sheets (Parentheticals) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Accounts receivable, allowance for doubtful account	$ 4,247	$ 3,148
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)	26,062,915	19,629,403
Common stock, shares outstanding (in shares)	26,062,915	19,629,403

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

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