Consolidated Balance Sheets (Parentheticals) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Allowance for doubtful accounts	$ 156	$ 149
Common stock, share authorized (in shares)	200,000,000	200,000,000
Common stock, par value (in dollars per share)	$ 0.001	$ 0.001
Common stock, share issued (in shares)	26,069,154	24,685,604
Common stock, share outstanding (in shares)	26,069,154	24,685,604