Properties Held for Sale and Property Dispositions (Details) $ in Millions	1 Months Ended	3 Months Ended	9 Months Ended
Jun. 30, 2023 USD ($) ft²	Sep. 30, 2023 USD ($) ft²	Sep. 30, 2023 USD ($) ft²
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Unaudited Approximate Usable Square Feet \| ft²		29,708,910	29,708,910
Ownership percentage deconsolidated	50.10%
Investment fair value adjustment	$ 17.0	$ 17.0	$ 17.0
245 Park Avenue
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Unaudited Approximate Usable Square Feet \| ft²	1,782,793
Sale Price	$ 1,995.0
Loss on Sale	$ (28.3)
Ownership interest sold	49.90%
Properties Sold
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Employee-related liabilities		$ 8.0	$ 8.0

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Equity Method Investment, Ownership Percentage, Deconsolidated

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Area of a real estate property.

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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 after tax of gain (loss) not previously recognized resulting from the disposal of a discontinued operation.

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Amount of consideration received or receivable for the disposal of assets and liabilities, including discontinued operation.

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Total of the carrying values as of the balance sheet date of obligations incurred through that date and payable for obligations related to services received from employees, such as accrued salaries and bonuses, payroll taxes and fringe benefits.

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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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