Condensed Consolidated Balance Sheets (Current Period Unaudited) (Parentheticals) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Trade, allowance	$ 3,191	$ 2,952
Preferred stock, par value (in dollars per share)	$ 0.01	$ 0.01
Preferred stock, authorized (in shares)	10,000,000	10,000,000
Preferred stock, issued (in shares)	0	0
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, authorized (in shares)	40,000,000	40,000,000
Common stock, issued (in shares)	11,658,768	11,656,160
Common stock, outstanding (in shares)	5,742,330	5,748,897
Treasury stock (in shares)	5,916,438	5,907,263

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

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