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Significant Accounting Policies (Tables) | 6 Months Ended
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Jun. 30, 2024
Accounting Policies [Abstract] |
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 June 30, 2024 and December 31, 2023 (in thousands):
| June 30, 2024 |  | December 31, 2023
Identified intangible assets (included in other assets): |  |  |
Gross amount | $ | 273,010 |  |  | $ | 189,680 |
Accumulated amortization | (189,425) |  |  | (184,902) |
Net | $ | 83,585 |  |  | $ | 4,778 |
Identified intangible liabilities (included in deferred revenue): |  |  |
Gross amount | $ | 226,034 |  |  | $ | 205,394 |
Accumulated amortization | (202,819) |  |  | (202,089) |
Net | $ | 23,215 |  |  | $ | 3,305 |
Schedule of Marketable Securities | As of June 30, 2024 and December 31, 2023, we held the following marketable securities (in thousands):
| June 30, 2024 |  | December 31, 2023
Commercial mortgage-backed securities | $ | 16,593 |  |  | $ | 9,591 |
Total investment in marketable securities | $ | 16,593 |  |  | $ | 9,591 |
Schedule of Properties Contributed of Annualized Cash Rent | For the three months ended June 30, 2024, 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 | Three months ended June 30, 2024
One Vanderbilt Avenue | 17.2%
11 Madison Avenue | 8.7%
420 Lexington Ave | 7.0%
1515 Broadway | 6.7%
245 Park Avenue | 5.9%
1185 Avenue of the Americas | 5.9%

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