Note 14 - Share-based Compensation - Stock Options Outstanding (Details)	3 Months Ended
	Dec. 31, 2018 $ / shares shares
Number Outstanding (in shares) | shares	2,639,924
Number Exercisable (in shares) | shares	1,702,236
Range One [Member]
Lower Exercise Price (in dollars per share)	$ 0.93
Upper Exercise Price (in dollars per share)	$ 1.69
Number Outstanding (in shares) | shares	603,198
Weighted Average Remaining Contractual Life (Year)	4 years 153 days
Weighted Average Exercise Price, Outstanding (in dollars per share)	$ 1.57
Number Exercisable (in shares) | shares	583,385
Weighted Average Exercise Price, Exercisable (in dollars per share)	$ 1.57
Range Two [Member]
Lower Exercise Price (in dollars per share)	1.71
Upper Exercise Price (in dollars per share)	$ 1.86
Number Outstanding (in shares) | shares	526,476
Weighted Average Remaining Contractual Life (Year)	3 years 193 days
Weighted Average Exercise Price, Outstanding (in dollars per share)	$ 1.80
Number Exercisable (in shares) | shares	455,601
Weighted Average Exercise Price, Exercisable (in dollars per share)	$ 1.81
Range Three [Member]
Lower Exercise Price (in dollars per share)	1.99
Upper Exercise Price (in dollars per share)	$ 1.99
Number Outstanding (in shares) | shares	1,125,000
Weighted Average Remaining Contractual Life (Year)	4 years 211 days
Weighted Average Exercise Price, Outstanding (in dollars per share)	$ 1.99
Number Exercisable (in shares) | shares	281,250
Weighted Average Exercise Price, Exercisable (in dollars per share)	$ 1.99
Range Four [Member]
Lower Exercise Price (in dollars per share)	2.02
Upper Exercise Price (in dollars per share)	$ 3.13
Number Outstanding (in shares) | shares	375,250
Weighted Average Remaining Contractual Life (Year)	2 years 262 days
Weighted Average Exercise Price, Outstanding (in dollars per share)	$ 2.56
Number Exercisable (in shares) | shares	372,000
Weighted Average Exercise Price, Exercisable (in dollars per share)	$ 2.56
Range Five [Member]
Lower Exercise Price (in dollars per share)	3.17
Upper Exercise Price (in dollars per share)	$ 3.17
Number Outstanding (in shares) | shares	10,000
Weighted Average Remaining Contractual Life (Year)	2 years 321 days
Weighted Average Exercise Price, Outstanding (in dollars per share)	$ 3.17
Number Exercisable (in shares) | shares	10,000
Weighted Average Exercise Price, Exercisable (in dollars per share)	$ 3.17