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Investments in Unconsolidated Joint Ventures (Impairments in Unconsolidated Joint Ventures) (Details)) - Unconsolidated Joint Ventures [Member] - USD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Schedule of Equity Method Investments [Line Items]
Impairment loss on investment	[1]	$ 341,338	$ 272,603	$ 50,705
CA-Colorado Center LLC[Member]
Schedule of Equity Method Investments [Line Items]
Impairment loss on investment		$ 168,391
capitlization rate		7.50%
Discount Rate		10.00%
Gateway Commons Complex [Member]
Schedule of Equity Method Investments [Line Items]
Impairment loss on investment		$ 126,163
capitlization rate		7.00%
Discount Rate		9.00%
Safeco Plaza REIT LLC
Schedule of Equity Method Investments [Line Items]
Impairment loss on investment		$ 46,784	$ 29,900
capitlization rate		7.00%
Discount Rate		8.00%
[1] During the year ended December 31, 2024, the Company recognized an other-than-temporary impairment loss on its investments in Colorado Center, Gateway Commons and Safeco Plaza of approximately $168.4 million, $126.1 million, and $46.8 million, respectively. During the year ended December 31, 2023, the Company recognized an other-than-temporary impairment loss on its investments in Platform 16, 360 Park Avenue South, 200 Fifth Avenue and Safeco Plaza of approximately $155.2 million, $54.0 million, $33.4 million and $29.9 million, respectively. During the year ended December 31, 2022, the Company recognized an other-than-temporary impairment loss on its investment in the unconsolidated joint venture that owns Dock 72 in Brooklyn, New York totaling approximately $50.7 million.

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