Investments in Unconsolidated Joint Ventures - Acquisition, Development and Construction Arrangements/Sale of Joint Venture Interest or Property (Details) - USD ($)	1 Months Ended	3 Months Ended
Mar. 31, 2021	Mar. 31, 2021	Mar. 31, 2020
Schedule of Equity Method Investments [Line Items]
Equity in net (loss) gain on sale of interest in unconsolidated joint venture/real estate		$ (12,629,000)	$ 0
55 West 46th Street, Tower 46 \| Joint venture
Schedule of Equity Method Investments [Line Items]
Ownership Interest Disposed	25.00%	25.00%
Gross Asset Valuation	$ 275,000.0	$ 275,000.0
Equity in net (loss) gain on sale of interest in unconsolidated joint venture/real estate	$ (15,200)

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

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The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

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Amount of gain (loss) on sale or disposal of an equity method investment.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
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-Section S99
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Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
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-Section S99
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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.

+ References

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