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		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Net income	$ 447,332	$ 95,365	$ 835,736	$ 699,517
Net (income) loss attributable to Noncontrolling Interests – Partially Owned Properties	$ (534)	$ (703)	$ (1,957)	$ (14,113)
Dilutive Securities Options	2,047	781	1,801	1,214
Denominator for net income per share – diluted	388,374	385,652	387,642	385,973
Net income per Unit – basic	$ 1.15	$ 0.24	$ 2.15	$ 1.77
Net income per Unit – diluted	$ 1.15	$ 0.24	$ 2.14	$ 1.77
ERPOP [Member]
Net income	$ 447,332	$ 95,365	$ 835,736	$ 699,517
Net (income) loss attributable to Noncontrolling Interests – Partially Owned Properties	(534)	(703)	(1,957)	(14,113)
Allocation to Preference Units	(773)	(773)	(2,318)	(2,318)
Numerator for net income per Unit – basic and diluted	$ 446,025	$ 93,889	$ 831,461	$ 683,086
Denominator for net income per Unit – basic	386,327	384,871	385,841	384,759
Dilutive Securities Options	2,047	781	1,801	1,214
Denominator for net income per share – diluted	388,374	385,652	387,642	385,973
Net income per Unit – basic	$ 1.15	$ 0.24	$ 2.15	$ 1.77
Net income per Unit – diluted	$ 1.15	$ 0.24	$ 2.14	$ 1.77