Note 1 - Summary of Significant Accounting Policies - Reconciliation of Earnings/(Loss) and the Weighted Average Number of Shares (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands		3 Months Ended								12 Months Ended
		Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Income from continuing operations										$ 299,353	$ 774,405	$ 384,506
Gain on sale of operating properties, net, net of tax										86,785	125,813	389
Net income attributable to noncontrolling interests										(7,288)	(6,028)	(11,879)
Discontinued operations attributable to noncontrolling interests												2,117
Preferred stock redemption charges											(5,816)
Preferred dividends										(46,220)	(57,084)	(58,294)
Income from continuing operations available to the common Shareholders										332,630	831,290	316,839
Earnings attributable to participating securities										(2,018)	(4,134)	(1,749)
Income from continuing operations available to common Shareholders										330,612	827,156	315,090
(Loss)/income from discontinued operations											(75)	48,868
Net income available to the Company’s common shareholders for basic earnings per share										$ 330,612	$ 827,081	$ 363,958
Weighted average common shares outstanding – basic (in shares)										418,402	411,319	409,088
-Basic (in dollars per share)										$ 0.79	$ 2.01	$ 0.77
Income from discontinued operations (in dollars per share)												0.12
Basic (in dollars per share)		$ 0.16	$ (0.13)	$ 0.46	$ 0.31	$ 0.87	$ 0.15	$ 0.27	$ 0.72	$ 0.79	$ 2.01	$ 0.89
Distributions on convertible units											$ 192	$ 529
Net income available to the Company’s common shareholders for diluted earnings per share										$ 330,612	$ 827,273	$ 364,487
Effect of dilutive securities (a): Equity awards (in shares)	[1]									1,307	1,414	1,227
Assumed conversion of convertible units (in shares)	[1]										118	723
Shares for diluted earnings per common share (in shares)	[1]									419,709	412,851	411,038
-Diluted (in dollars per share)										$ 0.79	$ 2	$ 0.77
Income from discontinued operations (in dollars per share)												0.12
Diluted (in dollars per share)		$ 0.16	$ (0.13)	$ 0.46	$ 0.31	$ 0.87	$ 0.15	$ 0.27	$ 0.71	$ 0.79	$ 2	$ 0.89

[1] The effect of the assumed conversion of certain convertible units had an anti-dilutive effect upon the calculation of Income from continuing operations per share. Accordingly, the impact of such conversions has not been included in the determination of diluted earnings per share calculations. Additionally, there were 3,490,400, 5,300,680 and 7,137,120, stock options that were not dilutive as of December 31, 2016, 2015 and 2014, respectively.