Note 2 - Earnings Per Share - Securities that Potentially Dilute Calculation of Diluted Earnings Per Share (Details) - shares	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Potentially dilute securities (in shares)	6,902,613	1,519,273
Share-based Payment Arrangement, Option [Member]
Potentially dilute securities (in shares)	1,561	2,311
Stock Appreciation Rights (SARs) [Member]
Potentially dilute securities (in shares)	132,566	132,559
Restricted Stock [Member]
Potentially dilute securities (in shares)		284,300
Convertible 2020/21 Notes [Member]
Potentially dilute securities (in shares)	6,713,817
Convertible 2020 Notes [Member]
Potentially dilute securities (in shares)		1,044,134
Warrant [Member]
Potentially dilute securities (in shares)	54,669	55,963
Warrants Classified as Equity [Member]
Potentially dilute securities (in shares)		6