Consolidated Statements of Cash Flows (Parentheticals) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Interest expense, capitalized amount	$ 10	$ 14	$ 10
Capital lease obligations for property and equipment	109	32	248
Non-cash stock options exercised	$ 397	$ 406	$ 900