Corporate Indebtedness - Schedule of Junior Subordinated Deferrable Interest Debentures and Principal Maturities (Details)	1 Months Ended	9 Months Ended
Jun. 30, 2005 USD ($)	Sep. 30, 2025 USD ($) quarter
Principal Repayments and Joint Venture Debt
Remaining 2025		$ 100,000,000
2026		655,148,000
2027		2,624,516,000
2028		284,663,000
2029		0
Thereafter		364,055,000
Total principal repayments		$ 4,028,382,000
Trust Preferred Securities
Debt Instrument [Line Items]
Proceeds from issuance of debt	$ 100,000,000.0
Interest rate added to base rate (as a percent)		0.26%
Interest payment deferment, number of consecutive quarters \| quarter		8
Due from joint venture
Principal Repayments and Joint Venture Debt
Remaining 2025		$ 10,085,000
2026		1,180,172,000
2027		1,742,323,000
2028		382,294,000
2029		0
Thereafter		2,490,300,000
Total principal repayments		5,805,174,000
Due from joint venture \| Mortgages and other loans payable
Scheduled Amortization
Remaining 2025		0
2026		0
2027		0
2028		0
2029		0
Thereafter		0
Total amortization of debt		0
Principal Repayments and Joint Venture Debt
Remaining 2025		0
2026		555,148,000
2027		1,184,516,000
2028		284,663,000
2029		0
Thereafter		264,055,000
Total principal repayments		2,288,382,000
Due from joint venture \| Revolving Credit Facility
Principal Repayments and Joint Venture Debt
Remaining 2025		0
2026		0
2027		390,000,000
2028		0
2029		0
Thereafter		0
Total principal repayments		390,000,000
Due from joint venture \| Unsecured Term Loans
Principal Repayments and Joint Venture Debt
Remaining 2025		0
2026		100,000,000
2027		1,050,000,000
2028		0
2029		0
Thereafter		0
Total principal repayments		1,150,000,000
Due from joint venture \| Trust Preferred Securities
Principal Repayments and Joint Venture Debt
Remaining 2025		0
2026		0
2027		0
2028		0
2029		0
Thereafter		100,000,000
Total principal repayments		100,000,000
Due from joint venture \| Senior Unsecured Notes
Principal Repayments and Joint Venture Debt
Remaining 2025		100,000,000
2026		0
2027		0
2028		0
2029		0
Thereafter		0
Total principal repayments		$ 100,000,000

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