Consolidated Statement of Capital Statement - USD ($) shares in Thousands, $ in Thousands	3 Months Ended	9 Months Ended
	Sep. 30, 2015	Sep. 30, 2015
Increase (Decrease) in Partner's Capital
Acquisition of subsidiary interest from noncontrolling interest		$ (20,650)
Other comprehensive loss	$ (5,106)	(9,190)
Issuance of common units		27,898
DRSPP proceeds		99,529
Conversion of units of the Operating Partnership to common stock		41,605
Reallocation of capital account relating to sale		(10,144)
Deferred compensation plan and stock award, net		(3,096)
Amortization of deferred compensation plan		20,994
Cash distributions to noncontrolling interests		$ (114,828)
Common Stock
Increase (Decrease) in Partner's Capital
DRSPP proceeds (in shares)		776
DRSPP proceeds		$ 8
Conversion of units of the Operating Partnership to common stock (in units)		353
Conversion of units of the Operating Partnership to common stock		$ 4
Deferred compensation plan and stock award, net (in shares)		28
Deferred compensation plan and stock award, net		$ 0
Contributions - net proceeds from common stock offering (in shares)		1,007
Contributions - proceeds from stock options exercised (in shares)		170
Noncontrolling Interests
Increase (Decrease) in Partner's Capital
Acquisition of subsidiary interest from noncontrolling interest		$ (11,084)
Reallocation of capital account relating to sale		(10,144)
Cash distributions to noncontrolling interests		(114,828)
SL Green Operating Partnership
Increase (Decrease) in Partner's Capital
Beginning Balance		7,928,740
Net income		198,894
Acquisition of subsidiary interest from noncontrolling interest		(20,650)
Other comprehensive loss	(5,106)	(9,190)
Preferred distributions		(11,214)
Issuance of common units		27,898
DRSPP proceeds		99,529
Conversion of units of the Operating Partnership to common stock		0
Reallocation of capital account relating to sale		(10,144)
Deferred compensation plan and stock award, net		(3,096)
Amortization of deferred compensation plan		20,994
Contribution to consolidated joint venture interest		34,435
Contributions - net proceeds from common stock offering		127,022
Contributions - proceeds from stock options exercised		12,870
Cash distributions to noncontrolling interests		(114,828)
Cash distributions declared ($1.80 per common unit, none of which represented a return of capital for federal income tax purposes)		(186,081)
Ending Balance	8,095,179	8,095,179
SL Green Operating Partnership | Series I Preferred Stock
Increase (Decrease) in Partner's Capital
Beginning Balance		221,932
Net income		11,214
Preferred distributions		(11,214)
Ending Balance	221,932	221,932
SL Green Operating Partnership | Common Stock | General Partner
Increase (Decrease) in Partner's Capital
Beginning Balance		$ 7,078,924
Beginning Balance (units)		97,325
Net income		$ 167,829
Acquisition of subsidiary interest from noncontrolling interest		$ (9,566)
DRSPP proceeds (in shares)		776
DRSPP proceeds		$ 99,529
Conversion of units of the Operating Partnership to common stock (in units)		353
Conversion of units of the Operating Partnership to common stock		$ 41,605
Deferred compensation plan and stock award, net (in shares)		28
Deferred compensation plan and stock award, net		$ (3,096)
Amortization of deferred compensation plan		$ 20,994
Contributions - net proceeds from common stock offering (in shares)		1,007
Contributions - net proceeds from common stock offering		$ 127,022
Contributions - proceeds from stock options exercised (in shares)		170
Contributions - proceeds from stock options exercised		$ 12,870
Cash distributions declared ($1.80 per common unit, none of which represented a return of capital for federal income tax purposes)		(179,064)
Ending Balance	$ 7,357,047	$ 7,357,047
Ending Balance (units)	99,659	99,659
SL Green Operating Partnership | Common Stock | Limited Partners
Increase (Decrease) in Partner's Capital
Beginning Balance		$ 113,298
Beginning Balance (units)		3,973
Net income		$ 6,634
Issuance of common units (in units)		255
Issuance of common units		$ 27,898
Conversion of units of the Operating Partnership to common stock (in units)		353
Conversion of units of the Operating Partnership to common stock		$ (41,605)
Cash distributions declared ($1.80 per common unit, none of which represented a return of capital for federal income tax purposes)		(7,017)
Ending Balance	$ 99,208	$ 99,208
Ending Balance (units)	3,875	3,875
SL Green Operating Partnership | Accumulated Other Comprehensive Loss
Increase (Decrease) in Partner's Capital
Beginning Balance		$ (7,256)
Other comprehensive loss		(9,190)
Ending Balance	$ (16,446)	(16,446)
SL Green Operating Partnership | Noncontrolling Interests
Increase (Decrease) in Partner's Capital
Beginning Balance		521,842
Net income		13,217
Acquisition of subsidiary interest from noncontrolling interest		(11,084)
Reallocation of capital account relating to sale		(10,144)
Contribution to consolidated joint venture interest		34,435
Cash distributions to noncontrolling interests		(114,828)
Ending Balance	$ 433,438	$ 433,438