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Significant Accounting Policies (Tables) | 12 Months Ended
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Dec. 31, 2024
Accounting Policies [Abstract] |
Schedule of Estimated Useful Lives | Properties other than Right of use assets - operating leases are depreciated using the straight-line method over the estimated useful lives of the assets. The estimated useful lives are as follows:
Category |  | Term
Building (fee ownership) |  | 40 years
Building improvements |  | shorter of remaining life of the building or useful life
Building (leasehold interest) |  | lesser of 40 years or remaining term of the lease
Right of use assets - financing leases |  | lesser of 40 years or remaining term of the lease
Furniture and fixtures |  | 4 to 7 years
Tenant improvements |  | shorter of remaining term of the lease or useful life
Schedule of Identified Intangible Assets and Intangible Liabilities | The following summarizes our identified intangible assets (acquired above-market leases and in-place leases) and intangible liabilities (acquired below-market leases) as of December 31, 2024 and 2023 (in thousands):
| December 31, 2024 |  | December 31, 2023
Identified intangible assets (included in other assets): |  |  |
Gross amount | $ | 378,277 |  |  | $ | 189,680 |
Accumulated amortization | (197,211) |  |  | (184,902) |
Net | $ | 181,066 |  |  | $ | 4,778 |
Identified intangible liabilities (included in deferred revenue): |  |  |
Gross amount | $ | 243,703 |  |  | $ | 205,394 |
Accumulated amortization | (204,092) |  |  | (202,089) |
Net | $ | 39,611 |  |  | $ | 3,305 |
Schedule of Estimated Annual Amortization of Acquired Above-market Leases, Net of Acquired Below-market Leases | The estimated annual amortization of acquired above-market leases, net of acquired (below-market) leases (a component of rental revenue), for each of the five succeeding years is as follows (in thousands):
2025 |  | $ | 5,828 |
2026 |  | 5,265 |
2027 |  | 4,754 |
2028 |  | 4,058 |
2029 |  | 3,719 |
Schedule of Estimated Annual Amortization of all Other Identifiable Assets | The estimated annual amortization of all other identifiable assets (a component of depreciation and amortization expense) including tenant improvements for each of the five succeeding years is as follows (in thousands):
2025 |  | $ | 30,485 |
2026 |  | 26,943 |
2027 |  | 21,648 |
2028 |  | 16,492 |
2029 |  | 15,008 |
Schedule of Marketable Securities | As of December 31, 2024 and 2023, we held the following marketable securities (in thousands):
| December 31, 2024 |  | December 31, 2023
Commercial mortgage-backed securities - available-for-sale | $ | 17,323 |  |  | $ | 9,591 |
Commercial mortgage-backed securities - held-to-maturity | 5,489 |  |  | — |
Total investment in marketable securities | $ | 22,812 |  |  | $ | 9,591 |
Schedule of Real Estate CMBS Securitization Trusts | As of December 31, 2024 and 2023, we consolidated the following CMBS securitization trusts (in thousands):
| December 31, 2024 |  | December 31, 2023 |  | Maturity |
Type | Fair Value (1) |  | Principal Value |  |  | Fair Value | Principal Value |  |  |
Real estate loans held by consolidated securitization vehicles | $ | 709,095 |  |  | $ | 894,000 |  |  |  | $ | — |  | $ | — |  |  |  | 2023 - 2024 | (2)
Senior obligations of consolidated securitization vehicles | 590,131 |  |  | 688,346 |  |  |  | — |  | — |  |  |  | 2023 - 2024 | (2)
Real estate loans held by consolidated securitization vehicles in excess of senior obligations of consolidated securitization vehicles | $ | 118,964 |  |  | $ | 205,654 |  |  |  | $ | — |  | $ | — |  |  |  |  |
(1)Includes $134.8 million and $34.2 million of assets and liabilities, respectively, for a loan that is on non-accrual and is accounted for on an amortized cost basis. (2)The Company is in discussions with the respective borrowers on the resolution of the past maturities.
Schedule of Properties Contributed of Annualized Cash Rent | For the years ended December 31, 2024, 2023, and 2022, the following properties contributed more than 5.0% of our annualized cash rent from office properties, including our share of annualized cash rent from joint venture office properties:
Property | 2024 | Property | 2023 | Property | 2022
One Vanderbilt Avenue | 14.7% | One Vanderbilt Avenue | 16.0% | One Vanderbilt Avenue | 14.1%
11 Madison Avenue | 8.8% | 11 Madison Avenue | 8.3% | 245 Park Avenue | 10.0%
420 Lexington Avenue | 7.0% | 420 Lexington Avenue | 6.7% | 11 Madison Avenue | 7.8%
1515 Broadway | 6.7% | 1515 Broadway | 6.4% | 420 Lexington Avenue | 6.3%
245 Park Avenue | 6.7% | 1185 Avenue of the Americas | 5.6% | 1515 Broadway | 5.8%
1185 Avenue of the Americas | 5.9% | 280 Park Avenue | 5.5% | 1185 Avenue of the Americas | 5.1%
280 Park Avenue | 5.2% | 245 Park Avenue | 5.5% | 280 Park Avenue | 5.1%

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