Note 19 - Stock-based Compensation - Stock Option Activities (Details) - USD ($)	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Outstanding (in shares)	164,410
Outstanding, weighted average exercise price (in dollars per share)	$ 14.68
Outstanding, average remaining contractual term (Year)	5 years	5 years 292 days
Outstanding, aggregate intrinsic value	$ 53,166	$ 37,316
Granted (in shares)	2,750
Granted, weighted average exercise price (in dollars per share)	$ 14.71
Exercised (in shares)	(8,460)
Exercised, weighted average exercise price (in dollars per share)	$ 10.39
Forfeited or expired (in shares)	(12,400)
Forfeited or expired, weighted average exercise price (in dollars per share)	$ 14.90
Outstanding (in shares)	146,300	164,410
Outstanding, weighted average exercise price (in dollars per share)	$ 14.92	$ 14.68
Exercisable (in shares)	57,910
Exercisable, weighted average exercise price (in dollars per share)	$ 14.91
Exercisable, average remaining contractual term (Year)	4 years 328 days
Exercisable, aggregate intrinsic value	$ 21,131