Condensed Consolidated Balance Sheets (Current Period Unaudited) (Parentheticals) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
Allowance for doubtful accounts	$ 2,955	$ 2,163
Preferred stock, par value (in dollars per share)	$ 0.01	$ 0.01
Preferred stock, authorized (in shares)	20,000,000	20,000,000
Preferred stock, issued (in shares)	0	0
Preferred stock, outstanding (in shares)	0	0
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, authorized (in shares)	200,000,000	200,000,000
Common stock issued (in shares)	20,153,269	20,153,269
Common stock, outstanding (in shares)	20,152,029	20,152,029
Treasury stock, shares (in shares)	1,240	1,240

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

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