Organization and Basis of Presentation (Details) - SL Green Operating Partnership	6 Months Ended
Jun. 30, 2016	Dec. 31, 2015
Organization
Percentage of ownership in SL Green Management LLC owned by operating partnership (percent)	100.00%
Noncontrolling interest in the operating partnership (as a percent)	4.30%	3.61%
Service Corporation
Organization
Economic interest in variable interest entity (as a percent)	95.00%

-- None. No documentation exists for this element. --

No definition available.

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- Definition

The equity interest of noncontrolling shareholders, partners or other equity holders in consolidated entity.

+ References

No definition available.

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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://www.xbrl.org/2003/role/presentationRef
-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

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- Definition

Percentage of the Variable Interest Entity's (VIE) voting interest owned by (or beneficial interest in) the reporting entity (directly or indirectly).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 810
-SubTopic 10
-Section 50
-Paragraph 5A
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=64801991&loc=SL6759159-111685

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