Debt (Summary of Debt) (Details) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Debt Instrument
Deferred financing costs, net and other	$ (54,746)	$ (58,268)
Total, net	6,050,693	6,053,343
Long term debt	$ 2,563,376	2,562,604
Mortgages
Debt Instrument
Interest rate, end of period (percent)	2.24%
Long-term debt, gross	$ 6,093,815	6,099,215
Deferred financing costs, net and other	(43,122)	(45,872)
Total, net	$ 6,050,693	6,053,343
Mortgages | Fixed Rate
Debt Instrument
Interest rate, end of period (percent)	2.80%
Long-term debt, gross	$ 2,190,000	2,190,000
Mortgages | Variable Rate
Debt Instrument
Interest rate, end of period (percent)	1.93%
Long-term debt, gross	$ 3,903,815	3,909,215
Senior Unsecured Notes
Debt Instrument
Interest rate, end of period (percent)	3.02%
Long-term debt, gross	$ 1,200,000	1,200,000
Deferred financing costs, net and other	(9,699)	(10,208)
Long term debt	$ 1,190,301	1,189,792
Unsecured term loan
Debt Instrument
Interest rate, end of period (percent)	3.72%
Long-term debt, gross	$ 800,000	800,000
Deferred financing costs, net and other	(1,925)	(2,188)
Long term debt	$ 798,075	797,812
Unsecured Revolving Credit Facilities
Debt Instrument
Interest rate, end of period (percent)	1.35%
Long term debt	$ 575,000	$ 575,000