Condensed Consolidated Balance Sheets (Parentheticals) - USD ($) $ in Thousands	Mar. 31, 2017	Dec. 31, 2016
Statement of Financial Position [Abstract]
Allowance for doubtful accounts	$ 1,581	$ 1,569
Accumulated depreciation	24,942	24,542
Accumulated amortization	$ 7,765	$ 7,257
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, shares authorized (in shares)	40,000,000	40,000,000
Common stock, shares issued (in shares)	23,914,256	23,800,924
Common stock outstanding (in shares)	23,533,883	23,446,035