Fair Value Measurements (Details) - USD ($) $ in Thousands	1 Months Ended	3 Months Ended	9 Months Ended
Jun. 30, 2023	Sep. 30, 2023	Sep. 30, 2023	Dec. 31, 2022
Fair Value of Financial Instruments
Marketable securities available-for-sale		$ 9,616	$ 9,616	$ 11,240
Interest rate cap and swap agreements (included in Other assets)		77,921	77,921	57,660
Interest rate cap and swap agreements (included in Other liabilities)		5,968	5,968	10,142
Debt and preferred equity investments		334,327	334,327	623,280
Ownership percentage deconsolidated	50.10%
Investment fair value adjustment	$ 17,000	17,000	17,000
245 Park Avenue
Fair Value of Financial Instruments
Ownership interest sold	49.90%
Carrying Value
Fair Value of Financial Instruments
Debt and preferred equity investments		334,327	334,327	623,280
Fixed rate debt		3,248,724	3,248,724	5,015,814
Variable rate debt		120,148	120,148	520,148
Total		3,368,872	3,368,872	5,535,962
Fair Value
Fair Value of Financial Instruments
Total		3,306,816	3,306,816	5,304,360
Estimated fair value of debt and preferred equity investments, low end of range		300,000	300,000	600,000
Estimated fair value of debt and preferred equity investments, high end of range		300,000	300,000	600,000
Level 1
Fair Value of Financial Instruments
Marketable securities available-for-sale		0	0	0
Interest rate cap and swap agreements (included in Other assets)		0	0	0
Interest rate cap and swap agreements (included in Other liabilities)		0	0	0
Level 2
Fair Value of Financial Instruments
Marketable securities available-for-sale		9,616	9,616	11,240
Interest rate cap and swap agreements (included in Other assets)		77,921	77,921	57,660
Interest rate cap and swap agreements (included in Other liabilities)		5,968	5,968	10,142
Level 3
Fair Value of Financial Instruments
Marketable securities available-for-sale		0	0	0
Interest rate cap and swap agreements (included in Other assets)		0	0	0
Interest rate cap and swap agreements (included in Other liabilities)		0	0	0
Level 3 \| Fair Value
Fair Value of Financial Instruments
Fixed rate debt		3,188,552	3,188,552	4,784,691
Variable rate debt		$ 118,264	$ 118,264	$ 519,669

Disposal Group, Including Discontinued Operation, Ownership Interest Disposed

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Equity Method Investment, Ownership Percentage, Deconsolidated

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Represents the high end of the range of estimated fair value for investments in mortgage loans on real estate.

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Represents the low end of the range of estimated fair value for investments in mortgage loans on real estate.

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Amount of addition (reduction) to the amount at which an asset could be incurred (settled) in a current transaction between willing parties.

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Amount excluding accrued interest, of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 326
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Fair value, before effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets elected not to be offset. Excludes assets not subject to a master netting arrangement.

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Fair value, before effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes liabilities elected not to be offset. Excludes liabilities not subject to a master netting arrangement.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission.

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The portion of the carrying amount of long-term borrowings outstanding as of the balance sheet date, including current maturities, which accrues interest at a set, unchanging rate.

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The portion of the carrying amount of long-term borrowings outstanding as of the balance sheet date, including current maturities, which accrues interest at a rate subject to change from time to time.

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The balance represents the amount of loans that are secured by real estate mortgages, offset by the reserve to cover probable credit losses on the loan portfolio.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 944
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