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Investment in Unconsolidated Joint Ventures (Narrative) (Details) $ in Thousands |  |  |  |  |  | 3 Months Ended | 7 Months Ended | 9 Months Ended | 12 Months Ended |
--- | --- | --- | --- | --- | --- | --- | --- | --- | --- | ---
Sep. 17, 2025 USD ($) | Aug. 20, 2025 | Jun. 27, 2025 USD ($) ft² apartments | Mar. 05, 2025 USD ($) ft² apartments | Feb. 27, 2025 USD ($) ft² | Sep. 30, 2025 USD ($) ft² Real_Estate_Properties | Sep. 30, 2024 USD ($) | Sep. 30, 2025 USD ($) ft² Real_Estate_Properties | Sep. 30, 2025 USD ($) ft² Real_Estate_Properties | Sep. 30, 2024 USD ($) | Dec. 31, 2024 USD ($) | Aug. 07, 2025 ft² floor
Schedule of Equity Method Investments [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Repayments of Secured Debt |  |  |  |  |  |  |  |  |  |  |  | $ 3,195 |  | $ 3,461 |  |
Loss from early extinguishment of debt |  |  |  |  |  |  | $ 0 |  | $ 0 |  |  | 338 |  | 0 |  |
Payments to Acquire Equity Method Investments |  |  |  |  |  |  |  |  |  |  |  | 118,524 |  | 87,498 |  |
Gains on sales of real estate |  |  |  |  |  |  | $ 1,932 |  | 517 |  |  | $ 20,322 |  | 517 |  |
Residential Building |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of real estate properties | Real_Estate_Properties |  |  |  |  |  |  | 9 |  |  | 9 |  | 9 |  |  |  |
7750 Wisconsin Avenue LLC [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Ownership Percentage |  |  |  |  |  | 50.00% | 50.00% |  |  | 50.00% |  | 50.00% |  |  |  |
CAB 290 Coles Venture LLC |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Ownership Percentage |  |  |  |  | 19.46% |  | 19.46% | [1] |  | 19.46% | [1] | 19.46% | [1] |  |  |
Payments to Acquire Equity Method Investments |  |  |  |  | $ 20,000 |  |  |  |  |  |  |  |  |  |  |
CAB 290 Coles Holdco LLC |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Ownership Percentage | [1],[2] |  |  |  |  |  | 0.00% |  |  | 0.00% |  | 0.00% |  |  |  |
Payments to Acquire Equity Method Investments |  |  |  |  |  |  |  |  |  | $ 11,900 |  |  |  |  |  |
CAB 290 Coles Holdco LLC | Maximum [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Payments to Acquire Equity Method Investments |  |  |  |  |  |  |  |  |  |  |  | $ 65,000 |  |  |  |
Internal Rate of return on preferred equity |  |  |  |  |  |  |  |  |  |  |  | 13.00% |  |  |  |
17 Hartwell Avenue JV LLC |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Ownership Percentage |  |  |  | 20.00% |  |  | 20.00% | [1] |  | 20.00% | [1] | 20.00% | [1] |  |  |
Contribution of Property |  |  |  | $ 5,600 |  |  |  |  |  |  |  |  |  |  |  |
17 Hartwell Avenue JV LLC | Joint Venture Partner [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Payments to Acquire Equity Method Investments |  |  |  | $ 23,000 |  |  |  |  |  |  |  |  |  |  |  |
360 PAS Holdco LLC |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Ownership Percentage |  |  |  |  |  |  | 71.11% | [3] |  | 71.11% | [3] | 71.11% | [3] |  |  | 71.11%
Podium Venture LLC [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Ownership Percentage |  |  | 50.00% |  |  |  | 50.00% | [4] |  | 50.00% | [4] | 50.00% | [4] |  |  |
Office Venture LLC |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Ownership Percentage |  |  | 50.00% |  |  |  | 50.00% | [4] |  | 50.00% | [4] | 50.00% | [4] |  |  |
Rosecrans-Sepulveda Partners 4, LLC |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Ownership Percentage |  | 50.00% |  |  |  |  | 50.00% | [5] |  | 50.00% | [5] | 50.00% | [5] |  |  |
Gateway Commons Complex [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Ownership Percentage | [6] |  |  |  |  |  | 50.00% |  |  | 50.00% |  | 50.00% |  |  |  |
Equity Method Investment, Other-than-Temporary Impairment |  |  |  |  |  |  | $ 145,100 |  |  |  |  | $ 145,100 |  |  | $ 126,100 |
Gateway Commons Complex [Member] | Maximum [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Other than Temporary Impairment Losses, Equity Method Investments, Capitalization Rate |  |  |  |  |  |  | 7.50% |  |  |  |  |  |  |  |  |
Other than Temporary Impairment Losses, Equity Method Investments, Discount Rate |  |  |  |  |  |  | 11.00% |  |  |  |  |  |  |  |  |
Gateway Commons Complex [Member] | Minimum [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Other than Temporary Impairment Losses, Equity Method Investments, Capitalization Rate |  |  |  |  |  |  | 6.50% |  |  |  |  |  |  |  |  |
Other than Temporary Impairment Losses, Equity Method Investments, Discount Rate |  |  |  |  |  |  | 10.00% |  |  |  |  |  |  |  |  |
Unconsolidated Joint Ventures [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Loss from early extinguishment of debt |  |  |  |  |  |  | $ 0 |  | 0 |  |  | 62 |  | 0 |  |
Gains on sales of real estate |  |  |  |  |  |  | 4,762 | [7] | 0 |  |  | 4,762 | [7] | 0 |  |
Equity Method Investment, Other-than-Temporary Impairment |  |  |  |  |  |  | 145,133 | [8] | $ 0 |  |  | 145,133 | [8] | $ 0 |  |
Unconsolidated Joint Ventures [Member] | Rosecrans-Sepulveda Partners 4, LLC |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Gains on sales of real estate |  |  |  |  |  |  | 2,200 |  |  |  |  |  |  |  |  |
7750 Wisconsin Avenue [Member] | Unconsolidated Properties |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Net Rentable Area (in sf) | ft² |  |  |  |  |  | 736,000 |  |  |  |  |  |  |  |  |  |
7750 Wisconsin Avenue [Member] | Unconsolidated Properties | Construction Loans |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Repayments of Secured Debt |  |  |  |  |  | $ 252,000 |  |  |  |  |  |  |  |  |  |
Loss from early extinguishment of debt |  |  |  |  |  |  |  |  |  |  |  | 100 |  |  |  |
7750 Wisconsin Avenue [Member] | Unconsolidated Properties | Mortgages [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt |  |  |  |  |  | $ 252,000 |  |  |  |  |  |  |  |  |  |
Debt Instrument, Interest Rate, Stated Percentage |  |  |  |  |  | 5.49% |  |  |  |  |  |  |  |  |  |
290 Coles Street | Unconsolidated Properties | Residential Building |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Net Rentable Area (in sf) | ft² |  |  |  |  | 560,000 |  |  |  |  |  |  |  |  |  |  |
Number of Units in Real Estate Property | apartments |  |  |  |  | 670 |  |  |  |  |  |  |  |  |  |  |
290 Coles Street | Unconsolidated Properties | Construction Loans |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument, Basis Spread on Variable Rate |  |  |  |  | 2.50% |  |  |  |  |  |  |  |  |  |  |
Debt |  |  |  |  | $ 225,000 |  |  |  |  |  |  |  |  |  |  |
Extension Option (in years) |  |  |  |  | 1 |  |  |  |  |  |  |  |  |  |  |
17 Hartwell Avenue |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Net Rentable Area (in sf) | ft² |  |  |  | 30,000 |  |  |  |  |  |  |  |  |  |  |  |
Proceeds from Sale, Real Estate, Held-for-Investment |  |  |  | $ 21,800 |  |  |  |  |  |  |  |  |  |  |  |
Gains on sales of real estate |  |  |  |  |  |  |  |  |  |  |  | 18,400 |  |  |  |
17 Hartwell Avenue | Unconsolidated Properties | Residential Building |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of Units in Real Estate Property | apartments |  |  |  | 312 |  |  |  |  |  |  |  |  |  |  |  |
17 Hartwell Avenue | Unconsolidated Properties | Construction Loans |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt |  |  |  | $ 98,700 |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument, Interest Rate, Stated Percentage |  |  |  | 6.75% |  |  |  |  |  |  |  |  |  |  |  |
360 Park Avenue South | Unconsolidated Properties |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Net Rentable Area (in sf) | ft² |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 450,000
Number of floors | floor |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 20
Hub on Causeway - Podium and 100 Causeway Street | Unconsolidated Properties | Construction Loans |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt |  |  |  |  |  |  | 490,000 |  |  | $ 490,000 |  | 490,000 |  |  |  |
Hub on Causeway - Podium and 100 Causeway Street | Unconsolidated Properties | Mortgages [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt |  |  |  |  |  |  | $ 465,000 |  |  | $ 465,000 |  | $ 465,000 |  |  |  |
Debt, Weighted Average Interest Rate |  |  |  |  |  |  | 5.733% |  |  | 5.733% |  | 5.733% |  |  |  |
100 Causeway Street | Unconsolidated Properties |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Net Rentable Area (in sf) | ft² |  |  |  |  |  |  | 634,000 |  |  | 634,000 |  | 634,000 |  |  |  |
100 Causeway Street | Unconsolidated Properties | Extended Maturity | Construction Loans |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument, Maturity Date |  |  | Oct. 20, 2025 |  |  |  |  |  |  |  |  |  |  |  |  |
Hub on Causeway - Podium | Unconsolidated Properties |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Net Rentable Area (in sf) | ft² |  |  |  |  |  |  | 383,000 |  |  | 383,000 |  | 383,000 |  |  |  |
Hub on Causeway - Podium | Unconsolidated Properties | Extended Maturity | Construction Loans |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument, Maturity Date |  |  | Oct. 23, 2025 |  |  |  |  |  |  |  |  |  |  |  |  |
Beach Cities Media Campus | Unconsolidated Properties |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Contractual Sale Price |  | $ 56,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |
Gains on sales of real estate |  | 4,800 |  |  |  |  |  |  |  |  |  |  |  |  |  |
Proceeds from Sale, Real Estate, Other, Held-for-Investment |  | 53,100 |  |  |  |  |  |  |  |  |  |  |  |  |  |
Beach Cities Media Campus | Unconsolidated Properties | Company's Share [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Gains on sales of real estate |  | 2,200 |  |  |  |  |  |  |  |  |  |  |  |  |  |
Proceeds from Sale, Real Estate, Other, Held-for-Investment |  | $ 26,600 |  |  |  |  |  |  |  |  |  |  |  |  |  |
[1] | This entity is a VIE (See Note 2).
[2] | The Company agreed to fund up to $65.0 million of the required capital through its preferred equity investment. The Company’s preferred equity investment will earn and accrue a 13.0% internal rate of return (“IRR”) and is to be redeemed, in full, upon the earlier of two years after stabilization of the property or March 5, 2030.
[3] | The Company’s ownership includes (1) a 35.79% direct interest in the joint venture, (2) an additional 35.02% indirect ownership in the joint venture, and (3) an additional 1.0% interest in the entity through which the partner owns its interest in the joint venture.
[4] | In conjunction with the execution of the mortgage loan signed on September 30, 2025 (described below), Podium Venture LLC and Office Venture LLC were created for structuring purposes and did not change any of the partner rights previously held by the partners of Podium Developer LLC or Office Tower Developer LLC, respectively.
[5] | On September 17, 2025, the joint venture completed the sale of Beach Cities Media Campus, a land parcel, located in El Segundo, California.
[6] | During the three months ended September 30, 2025, the Company recognized an other-than-temporary impairment loss on its investment.
[7] | During the three and nine months ended September 30, 2025, the joint venture recorded a gain on sale of real estate related to the Beach Cities Media Campus. As a result of the historical basis difference, the Company recognized a gain on sale of real estate totaling approximately $2.2 million, which consists of its share of the gain on sale reported by the joint venture as well as an adjustment for a basis differential.
[8] | During the three and nine months ended September 30, 2025, the Company recognized an other-than-temporary impairment loss on its investment in Gateway Commons of approximately $145.1 million.

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