Corporate Indebtedness - Junior Subordinated Deferrable Interest Debentures and Principal Maturities (Details)	1 Months Ended	12 Months Ended
Jun. 30, 2005 USD ($)	Dec. 31, 2021 USD ($) quarter
Principal Repayments and Joint Venture Debt
2022		$ 1,257,589,000
2023		56,583,000
2024		538,017,000
2025		100,812,000
2026		390,841,000
Thereafter		1,730,618,000
Repayments of principal		$ 4,074,460,000
Trust Preferred Securities
Debt Instrument [Line Items]
Proceeds from issuance of debt	$ 100,000,000
Trust Preferred Securities \| LIBOR
Debt Instrument [Line Items]
Interest rate added to base rate (as a percent)		125.00%
Interest payment deferment, number of consecutive quarters \| quarter		8
Joint venture
Principal Repayments and Joint Venture Debt
2022		$ 426,057,000
2023		750,696,000
2024		616,510,000
2025		1,391,185,000
2026		150,486,000
Thereafter		2,435,913,000
Repayments of principal		5,770,847,000
Joint venture \| Mortgages and other loans payable
Scheduled Amortization
2022		8,754,000
2023		6,583,000
2024		5,268,000
2025		812,000
2026		841,000
Thereafter		70,000
Future Amortization of Debt		22,328,000
Principal Repayments and Joint Venture Debt
2022		448,835,000
2023		50,000,000
2024		332,749,000
2025		0
2026		0
Thereafter		580,548,000
Repayments of principal		1,412,132,000
Joint venture \| Revolving Credit Facility
Principal Repayments and Joint Venture Debt
2022		0
2023		0
2024		0
2025		0
2026		390,000,000
Thereafter		0
Repayments of principal		390,000,000
Joint venture \| Unsecured Term Loans
Principal Repayments and Joint Venture Debt
2022		0
2023		0
2024		200,000,000
2025		0
2026		0
Thereafter		1,050,000,000
Repayments of principal		1,250,000,000
Joint venture \| Trust Preferred Securities
Principal Repayments and Joint Venture Debt
2022		0
2023		0
2024		0
2025		0
2026		0
Thereafter		100,000,000
Repayments of principal		100,000,000
Joint venture \| Senior Unsecured Notes
Principal Repayments and Joint Venture Debt
2022		800,000,000
2023		0
2024		0
2025		100,000,000
2026		0
Thereafter		0
Repayments of principal		$ 900,000,000

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The total expected future amortization of debt.

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The amount of amortization of debt expected to be recognized after the fifth full fiscal year following the date of the most recent balance sheet.

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The amount of amortization of debt expected to be recognized during the fifth full fiscal year following the date of the most recent balance sheet.

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The amount of amortization of debt expected to be recognized during the first full fiscal year following the date of the most recent balance sheet.

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The amount of amortization of debt expected to be recognized during the fourth full fiscal year following the date of the most recent balance sheet.

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The amount of amortization of debt expected to be recognized during the second full fiscal year following the date of the most recent balance sheet.

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Total amount of long-term debt maturing in future periods.

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Percentage points added to the reference rate to compute the variable rate on the debt instrument.

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