Consolidated Statements of Operations - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Revenues
Rental revenue, net	$ 279,407	$ 416,809	$ 560,736	$ 762,416
Escalation and reimbursement	42,620	48,616	86,812	94,227
Investment income	60,622	44,214	100,921	98,951
Other income	15,501	107,975	27,062	117,464
Total revenues	398,150	617,614	775,531	1,073,058
Expenses
Operating expenses, including related party expenses of $5,262 and $9,436 in 2017 and $6,667 and $10,129 in 2016.	70,852	75,324	145,358	154,844
Real estate taxes	60,945	62,124	122,013	123,798
Ground rent	8,308	8,307	16,616	16,615
Interest expense, net of interest income	64,856	89,089	130,478	183,761
Amortization of deferred financing costs	3,432	7,433	8,193	15,365
Depreciation and amortization	133,054	425,042	227,188	604,350
Transaction related costs	46	2,115	179	3,394
Marketing, general and administrative	24,256	24,484	48,399	48,516
Total expenses	365,749	693,918	698,424	1,150,643
Income (loss) before equity in net income from unconsolidated joint ventures, equity in net gain on sale of interest in unconsolidated joint venture/real estate, (loss) gain on sale of real estate, net, depreciable real estate reserves, and (loss) gain on sale of investment in marketable securities	32,401	(76,304)	77,107	(77,585)
Equity in net income from unconsolidated joint ventures	3,412	5,841	10,026	15,937
Equity in net gain on sale of interest in unconsolidated joint venture/real estate	13,089	33,448	15,136	43,363
(Loss) gain on sale of real estate, net	(3,823)	196,580	(3,256)	210,353
Depreciable real estate reserves	(29,064)	(10,387)	(85,336)	(10,387)
(Loss) gain on sale of investment in marketable securities	0	(83)	3,262	(83)
Net income	16,015	149,095	16,939	181,598
Net income attributable to noncontrolling interests:
Noncontrolling interests in the Operating Partnership	(419)	(5,586)	(895)	(6,508)
Noncontrolling interests in other partnerships	(786)	(3,435)	16,705	(5,409)
Preferred units distributions	(2,851)	(2,880)	(5,701)	(5,528)
Net income (loss) attributable to SL Green/SLGOP	11,959	137,194	27,048	164,153
Perpetual preferred stock dividends	(3,737)	(3,737)	(7,475)	(7,475)
Amounts attributable to SL Green common stockholders:
Income (loss) before depreciable real estate reserves and gains (losses) on sale	27,156	(77,056)	89,818	(76,947)
Equity in net gain on sale of interest in unconsolidated joint venture/real estate	12,517	32,058	14,474	41,634
(Loss) gain on sale of real estate, net	(3,656)	188,410	(3,114)	201,964
Depreciable real estate reserves	(27,795)	(9,955)	(81,605)	(9,973)
Net income attributable to SL Green common stockholders	$ 8,222	$ 133,457	$ 19,573	$ 156,678
Basic earnings per share:
Income (loss) from continuing operations before depreciable real estate reserves, gains on sale and discontinued operations (in usd per share)	$ 0.27	$ (0.77)	$ 0.90	$ (0.77)
Equity in net gain on sale of interest in unconsolidated joint venture/real estate (usd per share)	0.13	0.32	0.14	0.42
Gain on sale of real estate (in dollars per share)	(0.04)	1.88	(0.03)	2.02
Depreciable Real Estate Reserves, Effect on Earnings, Per Basic Share	(0.28)	(0.10)	(0.81)	(0.10)
Net income attributable to SL Green common stockholders (usd per share)	0.08	1.33	0.20	1.57
Diluted earnings per share:
Income (loss) from continuing operations before depreciable real estate reserves, gains on sale and discontinued operations (in usd per share)	0.27	(0.77)	0.89	(0.77)
Equity in net gain on sale of interest in unconsolidated joint venture/real estate (usd per share)	0.12	0.32	0.14	0.42
Gain on sale of real estate (in dollars per share)	(0.04)	1.88	(0.03)	2.01
Depreciable real estate reserves (in dollars per share)	(0.27)	(0.10)	(0.81)	(0.10)
Net income attributable to SL Green common stockholders (usd per share)	0.08	1.33	0.19	1.56
Dividends per share/unit (usd per share)	$ 0.775	$ 0.72	$ 1.55	$ 1.44
Basic weighted average common shares outstanding (in shares)	99,900	100,134	100,268	100,093
Diluted weighted average common shares and common share equivalents outstanding (in shares)	104,732	104,792	105,140	104,533
SL Green Operating Partnership
Revenues
Rental revenue, net	$ 279,407	$ 416,809	$ 560,736	$ 762,416
Escalation and reimbursement	42,620	48,616	86,812	94,227
Investment income	60,622	44,214	100,921	98,951
Other income	15,501	107,975	27,062	117,464
Total revenues	398,150	617,614	775,531	1,073,058
Expenses
Operating expenses, including related party expenses of $5,262 and $9,436 in 2017 and $6,667 and $10,129 in 2016.	70,852	75,324	145,358	154,844
Real estate taxes	60,945	62,124	122,013	123,798
Ground rent	8,308	8,307	16,616	16,615
Interest expense, net of interest income	64,856	89,089	130,478	183,761
Amortization of deferred financing costs	3,432	7,433	8,193	15,365
Depreciation and amortization	133,054	425,042	227,188	604,350
Transaction related costs	46	2,115	179	3,394
Marketing, general and administrative	24,256	24,484	48,399	48,516
Total expenses	365,749	693,918	698,424	1,150,643
Income (loss) before equity in net income from unconsolidated joint ventures, equity in net gain on sale of interest in unconsolidated joint venture/real estate, (loss) gain on sale of real estate, net, depreciable real estate reserves, and (loss) gain on sale of investment in marketable securities	32,401	(76,304)	77,107	(77,585)
Equity in net income from unconsolidated joint ventures	3,412	5,841	10,026	15,937
Equity in net gain on sale of interest in unconsolidated joint venture/real estate	13,089	33,448	15,136	43,363
(Loss) gain on sale of real estate, net	(3,823)	196,580	(3,256)	210,353
Depreciable real estate reserves	(29,064)	(10,387)	(85,336)	(10,387)
(Loss) gain on sale of investment in marketable securities	0	(83)	3,262	(83)
Net income	16,015	149,095	16,939	181,598
Net income attributable to noncontrolling interests:
Noncontrolling interests in the Operating Partnership			(895)
Noncontrolling interests in other partnerships	(786)	(3,435)	16,705	(5,409)
Preferred units distributions	(2,851)	(2,880)	(5,701)	(5,528)
Net income (loss) attributable to SL Green/SLGOP	12,378	142,780	27,943	170,661
Perpetual preferred unit distributions	(3,737)	(3,737)	(7,475)	(7,475)
Net income attributable to SLGOP common unitholders	8,641	139,043	20,468	163,186
Amounts attributable to SL Green common stockholders:
Income (loss) before depreciable real estate reserves and gains (losses) on sale	$ 28,439	$ 115,786	$ 93,924	$ (80,143)
Basic earnings per share:
Net income attributable to SLGOP common unitholders (usd per share)	$ 0.08	$ 1.33	$ 0.20	$ 1.57
Diluted earnings per share:
Net income attributable to SLGOP common unitholders (usd per share)	$ 0.08	$ 1.33	0.19	$ 1.56
Dividends per share/unit (usd per share)			$ 1.55
Basic weighted average common shares outstanding (in shares)	104,462	104,476	104,852	104,251
Basic weighted average common units outstanding (in shares)			104,852	104,251
Diluted weighted average common units and common unit equivalents outstanding (in shares)			105,140	104,533