Note 24 - Supplemental Financial Information (Unaudited) - Quarterly Results of Operations (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2020	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Revenues	$ 269,441	$ 259,792	$ 238,916	$ 289,744	$ 296,130	$ 282,871	$ 284,873	$ 295,010	$ 1,057,893	$ 1,158,884	$ 1,164,762
Net income/(loss) attributable to the Company	$ 201,234	$ (38,394)	$ 747,893	$ 90,100	$ 109,419	$ 83,990	$ 101,027	$ 116,169	$ 1,000,833	$ 410,605	$ 497,795
Basic (in dollars per share)	$ 0.46	$ (0.10)	$ 1.71	$ 0.19	$ 0.22	$ 0.14	$ 0.20	$ 0.24
Diluted (in dollars per share)	$ 0.45	$ (0.10)	$ 1.71	$ 0.19	$ 0.22	$ 0.14	$ 0.20	$ 0.24