Note 8 - Summary of Stock Options (Details) - Summary of Options Outstanding and Exercisable - Jun. 30, 2015 - $ / shares	Total
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Weighted Average Exercise Price, Options Outstanding	$ 0.88
Options Outstanding, Number (in Shares)	3,005,783
Weighted Average Remaining Contractural Term, Options Outstanding	8 years 357 days
Options Exercisable, Number (in Shares)	718,086
Weighted Average Exercise Price, Options Exercisable	$ 1.93
Range One [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Weighted Average Exercise Price, Options Outstanding	$ 0.33
Options Outstanding, Number (in Shares)	100,000
Weighted Average Remaining Contractural Term, Options Outstanding	9 years 317 days
Range Two [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Range of Exercise Prices, Lower Limit	$ 0.46
Weighted Average Exercise Price, Options Outstanding	0.47
Range of Exercise Prices, Upper Limit	$ 0.47
Options Outstanding, Number (in Shares)	635,000
Weighted Average Remaining Contractural Term, Options Outstanding	9 years 222 days
Range Three [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Weighted Average Exercise Price, Options Outstanding	$ 0.60
Options Outstanding, Number (in Shares)	1,881,476
Weighted Average Remaining Contractural Term, Options Outstanding	9 years 3 months
Options Exercisable, Number (in Shares)	328,779
Weighted Average Exercise Price, Options Exercisable	$ 0.60
Range Four [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Weighted Average Exercise Price, Options Outstanding	$ 1.24
Options Outstanding, Number (in Shares)	312,373
Weighted Average Remaining Contractural Term, Options Outstanding	7 years 146 days
Options Exercisable, Number (in Shares)	312,373
Weighted Average Exercise Price, Options Exercisable	$ 1.24
Range Five [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Range of Exercise Prices, Lower Limit	7.00
Weighted Average Exercise Price, Options Outstanding	8.64
Range of Exercise Prices, Upper Limit	$ 9.00
Options Outstanding, Number (in Shares)	57,603
Weighted Average Remaining Contractural Term, Options Outstanding	2 years 120 days
Options Exercisable, Number (in Shares)	57,603
Weighted Average Exercise Price, Options Exercisable	$ 8.64
Range Six [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Range of Exercise Prices, Lower Limit	12.00
Weighted Average Exercise Price, Options Outstanding	15.29
Range of Exercise Prices, Upper Limit	$ 18.63
Options Outstanding, Number (in Shares)	19,081
Weighted Average Remaining Contractural Term, Options Outstanding	2 years 299 days
Options Exercisable, Number (in Shares)	19,081
Weighted Average Exercise Price, Options Exercisable	$ 15.29
Range Seven [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Weighted Average Exercise Price, Options Outstanding	$ 37.00
Options Outstanding, Number (in Shares)	250
Weighted Average Remaining Contractural Term, Options Outstanding	2 years 87 days
Options Exercisable, Number (in Shares)	250
Weighted Average Exercise Price, Options Exercisable	$ 37.00