Consolidated Statement of Capital $ in Thousands	6 Months Ended
	Jun. 30, 2016 USD ($) shares
Increase (Decrease) in Partner's Capital
DRSPP proceeds	$ 89
Conversion of common units	11,795
Reallocation of noncontrolling interests in the operating partnership	(906)
Deferred compensation plan and stock award, net	(2,150)
Amortization of deferred compensation plan	12,823
Contribution to consolidated joint venture interests	1,434
Cash distributions to noncontrolling interests	$ (9,866)
Common Stock
Increase (Decrease) in Partner's Capital
DRSPP proceeds (in shares) | shares	1,000
Conversion of common units	$ 1
Deferred compensation plan and stock award, net (in shares) | shares	4,000
Contributions - proceeds from stock options exercised (in shares) | shares	74,000
Noncontrolling Interests
Increase (Decrease) in Partner's Capital
Contribution to consolidated joint venture interests	$ 1,434
Cash distributions to noncontrolling interests	(9,866)
SL Green Operating Partnership
Increase (Decrease) in Partner's Capital
Beginning Balance	7,719,317
Net income	169,562
Other comprehensive (loss)	(7,809)
Preferred distributions	(7,475)
DRSPP proceeds	89
Conversion of common units	11,755
Reallocation of noncontrolling interests in the operating partnership	(906)
Deferred compensation plan and stock award, net	(2,150)
Amortization of deferred compensation plan	12,823
Contribution to consolidated joint venture interests	1,434
Contributions - proceeds from stock options exercised	4,343
Cash distributions to noncontrolling interests	(9,866)
Cash distributions declared ($1.44 per common unit, none of which represented a return of capital for federal income tax purposes)	(143,998)
Ending Balance	7,747,119
SL Green Operating Partnership | Preferred Units | Series C Preferred Stock
Increase (Decrease) in Partner's Capital
Beginning Balance
Ending Balance
SL Green Operating Partnership | Preferred Units | Series I Preferred Stock
Increase (Decrease) in Partner's Capital
Beginning Balance	221,932
Ending Balance	221,932
SL Green Operating Partnership | Common Stock | Partners' Interest
Increase (Decrease) in Partner's Capital
Beginning Balance	$ 7,074,282
Beginning Balance (units) | shares	99,976,000
Net income	$ 164,153
Preferred distributions	$ (7,475)
DRSPP proceeds (in shares) | shares	1,000
DRSPP proceeds	$ 89
Conversion of common units (in shares) | shares	109,000
Conversion of common units	$ 11,755
Reallocation of noncontrolling interests in the operating partnership	$ (906)
Deferred compensation plan and stock award, net (in shares) | shares	4,000
Deferred compensation plan and stock award, net	$ (2,150)
Amortization of deferred compensation plan	$ 12,823
Contributions - proceeds from stock options exercised (in shares) | shares	74,000
Contributions - proceeds from stock options exercised	$ 4,343
Cash distributions declared ($1.44 per common unit, none of which represented a return of capital for federal income tax purposes)	(143,998)
Ending Balance	$ 7,112,916
Ending Balance (units) | shares	100,164,000
SL Green Operating Partnership | Accumulated Other Comprehensive Income (Loss)
Increase (Decrease) in Partner's Capital
Beginning Balance	$ (8,749)
Other comprehensive (loss)	(7,809)
Ending Balance	(16,558)
SL Green Operating Partnership | Noncontrolling Interests
Increase (Decrease) in Partner's Capital
Beginning Balance	431,852
Net income	5,409
Contribution to consolidated joint venture interests	1,434
Cash distributions to noncontrolling interests	(9,866)
Ending Balance	$ 428,829