Earnings Per Share and Earnings Per Unit - Computation of Net Income per Unit Basic and Net Income per Unit Diluted for Operating Partnership (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Net income	$ 332,671	$ 109,257
Net (income) loss attributable to Noncontrolling Interests – Partially Owned Properties	$ (12,530)	$ (799)
Dilutive Securities Options	2,363	2,707
Denominator for net income per share – diluted	386,949	385,184
Net income per Unit – basic	$ 0.83	$ 0.28
Net income per Unit – diluted	$ 0.83	$ 0.28
ERPOP [Member]
Net income	$ 332,671	$ 109,257
Net (income) loss attributable to Noncontrolling Interests – Partially Owned Properties	(12,530)	(799)
Allocation to Preference Units	(773)	(773)
Numerator for net income per Unit – basic and diluted	$ 319,368	$ 107,685
Denominator for net income per Unit – basic	384,586	382,477
Dilutive Securities Options	2,363	2,707
Denominator for net income per share – diluted	386,949	385,184
Net income per Unit – basic	$ 0.83	$ 0.28
Net income per Unit – diluted	$ 0.83	$ 0.28