Note 21 - Income Taxes - Taxable Income and Provisions for Income Taxes (Details) - USD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
(Loss)/income before income taxes – U.S.		$ (1,682)	$ 4,331	$ 1,487
Deferred		(1,100)
Federal tax benefit/(provision)		2,968	(2,876)	(1,592)
Total tax benefit/(provision) – U.S.		(3,317)	1,600	(880)
Net income		413,561	498,463	439,671
Taxable REIT Subsidiaries [Member]
Current		3,362	(1,221)	(704)
Deferred		(349)	(1,198)	(632)
Federal tax benefit/(provision)		3,013	(2,419)	(1,336)
Current		(26)	(43)	(66)
Deferred		(19)	(414)	(190)
State tax provision		(45)	(457)	(256)
Total tax benefit/(provision) – U.S.		2,968	(2,876)	(1,592)
Net income		1,286	1,455	(105)
(Loss)/income before taxes – Non-U.S.		(599)	2,384	(11,483)
Current	[1]	69	(1,634)	(2,425)
Deferred		(418)	358	(47)
Non-U.S. tax benefit		$ 349	$ 1,276	$ 2,472

[1] The year ended December 31, 2018 includes a charge of $1.6 million related to the recording of a deferred tax valuation allowance.