Condensed Consolidated Balance Sheets (Current Period Unaudited) (Parentheticals) - USD ($) shares in Thousands, $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Accounts receivable, allowance	$ 339	$ 332
Preferred stock, par value (in dollars per share)	$ 0.00015	$ 0.00015
Preferred stock, shares authorized (in shares)	5,000	5,000
Preferred stock, shares issued (in shares)	0	0
Preferred stock, shares outstanding (in shares)	0	0
Common stock, par value (in dollars per share)	$ 0.00015	$ 0.00015
Common stock, shares authorized (in shares)	70,000	70,000
Common stock, shares issued (in shares)	41,596	40,677
Common stock, shares outstanding (in shares)	32,350	32,382
Treasury stock, shares (in shares)	9,246	8,295

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

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