Consolidated Statement of Equity (USD $) In Thousands, except Share data	Total	Series C preferred stock	Series D preferred stock	Common Stock	Additional Paid-In-Capital	Treasury Stock	Accumulated Other Comprehensive Income (Loss)	Retained Earnings	Noncontrolling Interests	Comprehensive Income
Balance at Dec. 31, 2010	$ 5,397,544	$ 274,022	$ 96,321	$ 817	$ 3,660,842	$ (303,222)	$ (22,659)	$ 1,172,963	$ 518,460
Balance (in shares) at Dec. 31, 2010				78,307,000
Comprehensive Income:
Net income	629,302							622,433	6,869	629,302
Net unrealized loss on derivative instruments	(2,835)						(2,835)			(2,835)
SL Green's share of joint venture net unrealized gain on derivative instruments	3,417						3,417			3,417
Unrealized gains on marketable securities	488						488			488
Preferred dividends	(15,089)							(15,089)
Redemption of units and DRIP proceeds	731				731
Redemption of units and DRIP proceeds (in shares)				11,000
Reallocation of noncontrolling interest in the operating partnership	(42,296)							(42,296)
Deferred compensation plan & stock award, net	(3,652)			3	542	(4,197)
Deferred compensation plan & stock award, net (in shares)				249,000
Amortization of deferred compensation plan	16,831				16,831
Proceeds from issuance of common stock	419,463			56	419,407
Proceeds from issuance of common stock (in shares)				5,572,000
Proceeds from stock options exercised	7,091			2	7,089
Proceeds from stock options exercised (in shares)				158,000
Consolidation of joint venture interest	533								533
Cash distributions to noncontrolling interests	(133,712)								(133,712)
Cash distribution declared ($0.20 per common share, none of which represented a return of capital for federal income tax purposes)	(16,571)							(16,571)
Comprehensive income										630,372
Balance at Jun. 30, 2011	$ 6,261,245	$ 274,022	$ 96,321	$ 878	$ 4,105,442	$ (307,419)	$ (21,589)	$ 1,721,440	$ 392,150
Balance (in shares) at Jun. 30, 2011				84,297,000