Debt - Additional Information (Details)	3 Months Ended		9 Months Ended
	Sep. 30, 2021 USD ($) property	Sep. 30, 2020 USD ($)	Sep. 30, 2021 USD ($) property	Sep. 30, 2020 USD ($)	Aug. 31, 2021 USD ($)	Jul. 12, 2021 USD ($) property	Dec. 31, 2020 USD ($)	Dec. 31, 2007 USD ($)
Debt Instrument [Line Items]
Gain (loss) on extinguishment of debt	$ (13,222,000)	$ 17,557,000	$ (13,222,000)	$ 18,950,000
Debt repayment costs and fees			12,217,000	9,477,000
Capitalized interest			$ 2,124,000	$ 1,112,000
Disposal Group, Disposed of by Sale, Not Discontinued Operations | Properties Disposed by LCIF
Debt Instrument [Line Items]
Number of disposed properties encumbered with mortgage loan | property	2		2			2
Mortgages and Notes Payable
Debt Instrument [Line Items]
Weighted average interest rate	4.30%		4.30%				4.50%
Mortgages and notes payable	$ 117,275,000		$ 117,275,000				$ 138,412,000
Mortgage Loan | LCIF
Debt Instrument [Line Items]
Face amount of debt instrument						$ 11,610,000
Trust Preferred Securities | 6.804% Trust Preferred Securities
Debt Instrument [Line Items]
Face amount of debt instrument								$ 200,000,000
Interest rate, effective percentage	1.829%		1.829%
Principal amount outstanding	$ 129,120,000		$ 129,120,000				129,120,000
Unamortized debt issuance costs	1,550,000		$ 1,550,000				1,625,000
Trust Preferred Securities | London Interbank Offered Rate (LIBOR) | 6.804% Trust Preferred Securities
Debt Instrument [Line Items]
Basis spread on variable rate			1.70%
Senior Notes
Debt Instrument [Line Items]
Mortgages and notes payable	998,932,000		$ 998,932,000				787,688,000
Initial discount	$ 3,760,000		$ 3,760,000				3,491,000
Senior Notes | Senior Notes Due 2031
Debt Instrument [Line Items]
Stated interest rate	2.375%		2.375%		2.375%
Mortgages and notes payable	$ 400,000,000		$ 400,000,000		$ 400,000,000		0
Percentage of issuance price	99.758%		99.758%		99.758%
Initial discount					$ 968,000
Senior Notes | Senior Notes Due 2023 and Senior Notes Due 2024
Debt Instrument [Line Items]
Accrued and unpaid interest		1,024,000
Gain (loss) on extinguishment of debt		10,066,000
Debt repayment costs and fees		9,477,000
Senior Notes | Senior Notes Due 2023
Debt Instrument [Line Items]
Stated interest rate	4.25%		4.25%
Mortgages and notes payable	$ 0		$ 0				188,756,000
Percentage of issuance price	99.026%		99.026%
Aggregate principal of debt redeemed	$ 188,756,000	$ 61,244,000
Repayment of debt, make-whole premium	12,191,000
Accrued and unpaid interest	2,028,000
Gain (loss) on extinguishment of debt	12,948,000
Senior Notes | Senior Notes Due 2024
Debt Instrument [Line Items]
Stated interest rate		4.40%		4.40%
Mortgages and notes payable	$ 198,932,000		$ 198,932,000				198,932,000
Percentage of issuance price	99.883%		99.883%
Aggregate principal of debt redeemed		$ 51,068,000
Senior Notes | Senior Notes Due 2030
Debt Instrument [Line Items]
Stated interest rate	2.70%		2.70%
Mortgages and notes payable	$ 400,000,000		$ 400,000,000				$ 400,000,000
Percentage of issuance price	99.233%		99.233%
Initial discount	$ 3,068,000		$ 3,068,000
Minimum | Mortgages and Notes Payable
Debt Instrument [Line Items]
Stated interest rate	3.50%		3.50%				3.50%
Maximum | Mortgages and Notes Payable
Debt Instrument [Line Items]
Stated interest rate	5.40%		5.40%				6.30%