Reconciliation of net income to taxable income (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Income Tax Disclosure [Abstract]
Net income (loss)	$ 404,047	$ 402,793	$ 194,204
Net income attributable to noncontrolling interest	$ (40,882)	(23,481)	(25,111)
Rental revenue recognition		(65,901)	(121,589)
Depreciation and amortization		161,514	137,576
Stock-based compensation		30,771	23,466
Interest expense		(6,414)	(5,256)
Sales of property		(39,393)	12,166
Impairments		0	9,011
Unrealized (gains)/losses on non-real estate investments		(95,757)	0
Other		(5,043)	3,642
Taxable income, before dividend deduction		359,089	228,109
Dividend deduction necessary to eliminate taxable income		(359,089)	(228,109)
Estimated income subject to federal income tax		0	0
Common stock and preferred stock distributions paid		$ 385,800	$ 321,800