Note 11 - Stock-Based Compensation - Stock Option Award Activity (Details) - shares	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Options outstanding (in shares)			2,313
Granted (in shares)	0	0	0	0
Canceled or forfeited (in shares)			(749)
Exercised (in shares)
Options outstanding (in shares)	1,564		1,564
Weighted-average remaining contractual life (in years) (Year)			5 years 255 days