Investments in Real Estate Partnerships - Scheduled Principal Repayments on Notes Payable (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Schedule of Equity Method Investments [Line Items]
2023	$ 69,078
2024	345,607
2025	297,982
2026	316,287
2027	666,703
Beyond 5 Years	2,053,192
Unamortized debt premium/(discount) and issuance costs	(22,095)
Total	3,726,754	$ 3,718,944
Unsecured Debt [Member]
Schedule of Equity Method Investments [Line Items]
Total	3,248,373	$ 3,243,991
Unconsolidated Investments in Partnership [Member]
Schedule of Equity Method Investments [Line Items]
2023	128,302
2024	35,895
2025	143,116
2026	246,490
2027	36,602
Beyond 5 Years	818,844
Unamortized debt premium/(discount) and issuance costs	(10,952)
Total	1,398,297
Unconsolidated Investments in Partnership [Member] \| Mortgages [Member] \| Scheduled Principal Payments [Member]
Schedule of Equity Method Investments [Line Items]
2023	3,194
2024	2,205
2025	3,433
2026	3,807
2027	3,802
Beyond 5 Years	9,194
Unamortized debt premium/(discount) and issuance costs	0
Total	25,635
Unconsolidated Investments in Partnership [Member] \| Mortgages [Member] \| Mortgage Loan Maturities [Member]
Schedule of Equity Method Investments [Line Items]
2023	125,108
2024	33,690
2025	139,683
2026	218,883
2027	32,800
Beyond 5 Years	809,650
Unamortized debt premium/(discount) and issuance costs	(10,952)
Total	1,348,862
Unconsolidated Investments in Partnership [Member] \| Unsecured Debt [Member] \| Unsecured Maturities [Member]
Schedule of Equity Method Investments [Line Items]
2023	0
2024	0
2025	0
2026	23,800
2027	0
Beyond 5 Years	0
Unamortized debt premium/(discount) and issuance costs	0
Total	23,800
Unconsolidated Investments in Partnership, Pro-rata Share [Member] [Member]
Schedule of Equity Method Investments [Line Items]
2023	51,187
2024	14,298
2025	43,908
2026	79,741
2027	12,420
Beyond 5 Years	300,506
Unamortized debt premium/(discount) and issuance costs	(3,800)
Total	$ 498,260

Amount, after accumulated amortization, of debt discount (premium).

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