Note 11 - Earnings Per Share (Details Textual) - shares shares in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016	Mar. 28, 2017	Mar. 17, 2017	Dec. 31, 2016
Restricted Stock and Deferred Shares Granted to Directors [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount			2,976
6.25% Convertible Notes Due 2018 [Member]
Debt Instrument, Interest Rate, Stated Percentage	6.25%		6.25%		6.25%	6.25%	6.25%
6.25% Convertible Notes Due 2018 [Member] | Convertible Notes Payable [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount	977	9,143	4,118	9,298
Debt Instrument, Interest Rate, Stated Percentage	6.25%		6.25%