Note 9 - Stock-based Compensation Plans and Warrants - Summary of Stock Option Activity (Details) - USD ($)	12 Months Ended
	Dec. 31, 2016		Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Outstanding (in shares)	507,500		822,500	842,500
Outstanding (in dollars per share)	$ 11.66		$ 11.82	$ 11.84
Outstanding (Year)	3 years 109 days		4 years 109 days	3 years 146 days	4 years 182 days
Outstanding	$ 3,934		$ 7,181,000	$ 7,316,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross	0		0	0
Granted (in dollars per share)
Forfeited, Expired or canceled (in shares)			(315,000)	(20,000)
Forfeited, Expired or canceled (in dollars per share)			$ 12.09	$ 12.60
Forfeited, Expired or canceled (Year)	3 years 109 days
Forfeited, Expired or canceled			$ 3,247,000	$ 135,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period	0
Exercised (in dollars per share)
Outstanding (in shares)	507,500	[1]	507,500	822,500	842,500
Outstanding (in dollars per share)	$ 11.66		$ 11.66	$ 11.82	$ 11.84
Outstanding	$ 3,394,000		$ 3,934	$ 7,181,000	$ 7,316,000
Options exercisable at December 31, 2016 (in shares)	507,500
Options exercisable at December 31, 2016 (in dollars per share)	$ 11.66
Options exercisable at December 31, 2016	$ 3,394,000
Weighted-average years of remaining contractual life of options outstanding at December 31, 2016 (Year)	3 years 109 days

[1] Exercise Prices vary from $9.88 to $12.51, and expiration dates vary from January 2020 to December 2021.