Note 1 - Summary of Significant Interim Accounting Policies - Stock Option Activity (Details) - $ / shares	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Outstanding (in shares)			946,546
Outstanding (in dollars per share)			$ 8.39
Granted (in shares)	52,530	50,310	172,862	103,308
Granted (in dollars per share)			$ 16.53
Exercised (in shares)			(178,179)
Exercised (in dollars per share)			$ 7.55
Lapsed (in shares)			(11,131)
Lapsed (in dollars per share)			$ 5.92
Cancelled (in shares)			(3,260)
Cancelled (in dollars per share)			$ 17.53
Outstanding (in shares)	926,838		926,838
Outstanding (in dollars per share)	$ 10.06		$ 10.06