Note 11 - Subsequent Events (Details) (USD $)	9 Months Ended		0 Months Ended		2 Months Ended			0 Months Ended
	Sep. 30, 2014	Dec. 31, 2013	Oct. 27, 2014 IPO [Member] Subsequent Event [Member]	Oct. 21, 2014 IPO [Member] Subsequent Event [Member]	Nov. 21, 2014 IPO [Member] Subsequent Event [Member]	Oct. 27, 2014 IPO [Member] Subsequent Event [Member]	Oct. 21, 2014 IPO [Member] Subsequent Event [Member]	Oct. 03, 2014 Subsequent Event [Member] Maximum [Member] The 2014 Employee Stock Purchase Plan [Member]	Oct. 03, 2014 Subsequent Event [Member] The 2014 Employee Stock Purchase Plan [Member]	Oct. 03, 2014 Subsequent Event [Member] The 2014 Employee Stock Purchase Plan [Member]
Note 11 - Subsequent Events (Details) [Line Items]
Stock Issued During Period, Shares, New Issues			6,110,000	7,026,500
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period	709			916,500
Share Price (in Dollars per share)							$ 10
Stock Issued During Period, Value, New Issues (in Dollars)				$ 70,300,000
Proceeds from Issuance of Common Stock (in Dollars)					62,500,000
Payments of Stock Issuance Costs (in Dollars)	$ 452,000				$ 7,700,000
Stock Issued During Period Shares Warrants Exercised			498,889
Class of Warrant or Right, Exercise Price of Warrants or Rights (in Dollars per share)						$ 4.60
Conversion of Stock, Shares Issued				8,651,805
Common Stock, Capital Shares Reserved for Future Issuance	10,634,030,000	5,810,472,000								704,000
Common Stock, Capital Shares Reserved for Future Issuance, Outstanding Common Stock, Percentage									4.00%
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized										140,500
Share-based Compensation Arrangement by Share-based Payment Award, Additional Shares Authorized, Common Stock Outstanding, Percentage									1.00%
Share-based Compensation Arrangement by Share-based Payment Award, Number of Additional Shares Authorized								281,000