Corporate Indebtedness - Schedule of Junior Subordinated Deferrable Interest Debentures and Principal Maturities (Details)	1 Months Ended
Jun. 30, 2005 USD ($) quarter	Mar. 31, 2024 USD ($)
Principal Repayments and Joint Venture Debt
Remaining 2024		$ 586,230,000
2025		470,000,000
2026		190,148,000
2027		2,250,000,000
2028		205,000,000
Thereafter		100,000,000
Total principal repayments		3,801,378,000
Trust Preferred Securities
Debt Instrument [Line Items]
Proceeds from issuance of debt	$ 100,000,000
Trust Preferred Securities \| SOFR
Debt Instrument [Line Items]
Interest rate added to base rate (as a percent)	0.26%
Interest payment deferment, number of consecutive quarters \| quarter	8
Joint venture
Principal Repayments and Joint Venture Debt
Remaining 2024		1,488,241,000
2025		1,739,239,000
2026		544,400,000
2027		1,185,168,000
2028		0
Thereafter		2,130,300,000
Total principal repayments		7,087,348,000
Joint venture \| Mortgages and other loans payable
Scheduled Amortization
Remaining 2024		2,987,000
2025		0
2026		0
2027		0
2028		0
Thereafter		0
Total amortization of debt		2,987,000
Principal Repayments and Joint Venture Debt
Remaining 2024		383,243,000
2025		370,000,000
2026		190,148,000
2027		550,000,000
2028		205,000,000
Thereafter		0
Total principal repayments		1,698,391,000
Joint venture \| Revolving Credit Facility
Principal Repayments and Joint Venture Debt
Remaining 2024		0
2025		0
2026		0
2027		650,000,000
2028		0
Thereafter		0
Total principal repayments		650,000,000
Joint venture \| Unsecured Term Loans
Principal Repayments and Joint Venture Debt
Remaining 2024		200,000,000
2025		0
2026		0
2027		1,050,000,000
2028		0
Thereafter		0
Total principal repayments		1,250,000,000
Joint venture \| Trust Preferred Securities
Principal Repayments and Joint Venture Debt
Remaining 2024		0
2025		0
2026		0
2027		0
2028		0
Thereafter		100,000,000
Total principal repayments		100,000,000
Joint venture \| Senior Unsecured Notes
Principal Repayments and Joint Venture Debt
Remaining 2024		0
2025		100,000,000
2026		0
2027		0
2028		0
Thereafter		0
Total principal repayments		$ 100,000,000

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