Note 7 - Employee Benefit Plans - Stock Options Activity (Details) - USD ($) $ / shares in Units, shares in Thousands	9 Months Ended
	Sep. 30, 2020
Outstanding (in shares)	745
Outstanding, weighted average exercise price (in dollars per share)	$ 10.64
Granted (weighted average fair value of $5.75 per share) (in shares)	24
Granted (weighted average fair value of $5.75 per share) (in dollars per share)	$ 16.72
Exercised (in shares)	(177)
Exercised, weighted average exercise price (in dollars per share)	$ 10.33
Canceled (in shares)	(43)
Canceled, weighted average exercise price (in dollars per share)	$ 10.69
Expired (in shares)	(10)
Expired, weighted average exercise price (in dollars per share)	$ 10.06
Outstanding, weighted average exercise price (in dollars per share)	$ 11.02
Outstanding, weighted average remaining contractual (Year)	3 years 6 months 21 days
Outstanding, aggregate intrinsic value	$ 4,188
Vested and expected to vest (in shares)	531
Vested and expected to vest, weighted average exercise price (in dollars per share)	$ 10.96
Vested and expected to vest, weighted average remaining contractual term (Year)	3 years 5 months 23 days
Vested and expected to vest, aggregate intrinsic value	$ 4,158,000
Exercisable (in shares)	433
Exercisable, weighted average exercise price (in dollars per share)	$ 10.08
Exercisable, weighted average remaining contractual term (Year)	2 years 3 months 25 days
Exercisable, aggregate intrinsic value	$ 3,779,000