Organization and Basis of Presentation (Details)	1 Months Ended	6 Months Ended
Jun. 30, 1997 Service Corporation	Jun. 30, 2011 SL Green Operating Partnership	Dec. 31, 2010 SL Green Operating Partnership
Organization
Economic interest in variable interest entity (as a percent)	95.00%
Percentage of ownership in SL Green Management LLC owned by operating partnership (as a percent)		100.00%
Noncontrolling interest in the operating partnership (as a percent)		2.22%	1.57%

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

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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 SEC
-Name Regulation S-X (SX)
-Number 210
-Section 22
-Article 12

+ Details

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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=6970148&loc=SL6759159-111685

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