Note 20 - Incentive Plans - Restricted Stock Activity (Details) - Restricted Stock [Member] - shares		12 Months Ended
		Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Restricted stock outstanding as of January 1, (in shares)		1,777,429	1,930,732	1,712,534
Granted (1) (in shares)	[1]	1,100,590	646,142	756,530
Vested (in shares)		(751,201)	(783,872)	(520,539)
Forfeited (in shares)		(21,904)	(15,573)	(17,793)
Restricted stock outstanding as of December 31, (in shares)		2,104,914	1,777,429	1,930,732

[1] The weighted-average grant date fair value for restricted stock issued during the years ended December 31, 2018, 2017 and 2016 were $14.73, $25.04 and $26.15, respectively.