Note 3 - Restatement - Effects of Restatement (Details) (Parentheticals) - $ / shares	Mar. 31, 2020	Dec. 31, 2019	Mar. 31, 2019
Preferred stock, par value (in dollars per share)	$ 0.01	$ 0.01	$ 0.01
Preferred stock, authorized (in shares)	3,000,000	3,000,000	3,000,000
Preferred stock, outstanding (in shares)	0	0	0
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01	$ 0.01
Common stock, shares authorized (in shares)	150,000,000	150,000,000	150,000,000
Common stock, shares issued (in shares)	45,592,292	45,503,805	46,812,366
Common stock, shares outstanding (in shares)	45,592,292	45,503,805	46,812,366