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v3.20.2

Organization and Basis of Presentation - Additional Information (Details) | 9 Months Ended |
--- | --- | ---
Sep. 30, 2020 | Dec. 31, 2019
Service Corporation |  |
Organization |  |
Percentage of ownership in SL Green Management LLC owned by operating partnership (percent) | 95.00% |
Operating Partnership | SL Green Operating Partnership |  |
Organization |  |
Noncontrolling interest in the operating partnership (as a percent) | 5.23% | 5.03%
SL Green Management | SL Green Management LLC |  |
Organization |  |
Percentage of ownership in SL Green Management LLC owned by operating partnership (percent) | 100.00% |

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- Definition The number of units or percentage investment held in the subsidiary by the limited liability company or limited partnership. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 946 -SubTopic 320 -Section S99 -Paragraph 9 -URI http://asc.fasb.org/extlink&oid=50485924&loc=d3e611443-123010 + Details
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