Note 18 - Employee Benefit Plans - Stock Option Activity (Details) - $ / shares	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Balance outstanding, weighted average exercise price (in dollars per share)	$ 0	$ 5.14	$ 15.74
Granted, weighted average exercise price (in dollars per share)	0	0	0
Exercised, weighted average exercise price (in dollars per share)	0	5.12	7.07
Forfeited, weighted average exercise price (in dollars per share)	0	0	28.71
Balance outstanding, weighted average exercise price (in dollars per share)	0	$ 0	$ 5.14
Options exercisable, weighted average exercise price (in dollars per share)	$ 0
Incentive Stock Options [Member]
Balance outstanding (in shares)	0	12,500	46,000
Granted (in shares)	0	0	0
Exercised (in shares)	0	(12,500)	(13,500)
Forfeited (in shares)	0	0	(20,000)
Balance outstanding (in shares)	0	0	12,500
Options exercisable (in shares)	0
Non-Incentive Stock Options [Member]
Balance outstanding (in shares)	0	5,000	25,000
Granted (in shares)	0	0	0
Exercised (in shares)	0	(5,000)	(10,000)
Forfeited (in shares)	0	0	(10,000)
Balance outstanding (in shares)	0	0	5,000
Options exercisable (in shares)	0