Consolidated Statements of Income (USD $) In Thousands, except Per Share data, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Revenues
Rental revenue, net	$ 1,077,976	$ 961,935	$ 782,530
Escalation and reimbursement	167,388	145,596	118,212
Investment and preferred equity income	119,155	120,418	147,926
Other income	35,736	35,479	35,718
Total revenues	1,400,255	1,263,428	1,084,386
Expenses
Operating expenses (including $18,101 (2012), $16,266 (2011) and $14,320 (2010) paid to related parties)	298,322	263,709	224,693
Real estate taxes	210,467	174,454	145,830
Ground rent	37,866	32,919	31,191
Interest expense, net of interest income	330,569	285,917	230,648
Amortization of deferred financing costs	19,450	14,118	9,046
Depreciation and amortization	332,028	277,345	225,193
Loan loss and other investment reserves, net of recoveries	564	6,722	17,751
Transaction related costs	5,625	5,561	11,849
Marketing, general and administrative	82,840	80,103	75,946
Total expenses	1,317,731	1,140,848	972,147
Income from continuing operations before equity in net income of unconsolidated joint ventures, gains on sale, purchase price fair value adjustment, depreciable real estate reserves, gain (loss) on early extinguishment of debt, noncontrolling interests and discontinued operations	82,524	122,580	112,239
Equity in net income from unconsolidated joint ventures	76,418	1,583	39,607
Equity in net gain on sale of interest in unconsolidated joint venture/ real estate	37,053	2,918	128,921
Purchase price fair value adjustment		498,195
Gain on sale of investment in marketable securities	4,940	4,866	490
Depreciable real estate reserves		(5,789)	(2,750)
Gain (loss) on early extinguishment of debt	(6,978)	904	(1,900)
Income from continuing operations	193,957	625,257	276,607
Net income from discontinued operations	9,116	5,780	7,064
Gain on sale of discontinued operations	6,627	46,085	35,485
Net income	209,700	677,122	319,156
Net income attributable to noncontrolling interests:
Noncontrolling interests in the operating partnership	(5,597)	(14,629)	(4,574)
Noncontrolling interests in other partnerships	(5,591)	(15,083)	(14,007)
Preferred units distribution	(2,107)
Net income attributable to SL Green	196,405	647,410	300,575
Preferred stock redemption costs	(10,010)
Preferred stock dividends	(30,411)	(30,178)	(29,749)
Net income attributable to SL Green common stockholders	155,984	617,232	270,826
Amounts attributable to SL Green common stockholders:
Income from continuing operations	105,019	65,523	102,208
Purchase price fair value adjustment		498,195
Gain on sale of unconsolidated joint ventures/ real estate	35,769	2,850	126,778
Net income from discontinued operations	8,799	5,646	6,946
Gain on sale of discontinued operations	6,397	45,018	34,894
Net income attributable to SL Green common stockholders	$ 155,984	$ 617,232	$ 270,826
Basic earnings per share:
Net income from continuing operations before gains on sale and discontinued operations (in dollars per share)	$ 1.18	$ 6.73	$ 1.31
Equity in net gain on sale of interest in unconsolidated joint venture/real estate (in dollars per share)	$ 0.40	$ 0.03	$ 1.62
Net income from discontinued operations (in dollars per share)	$ 0.10	$ 0.07	$ 0.09
Gain on sale of discontinued operations (in dollars per share)	$ 0.07	$ 0.54	$ 0.45
Net income attributable to SL Green common stockholders (in dollars per share)	$ 1.75	$ 7.37	$ 3.47
Diluted earnings per share:
Net income from continuing operations before gains on sale and discontinued operations (in dollars per share)	$ 1.17	$ 6.70	$ 1.30
Equity in net gain on sale of interest in unconsolidated joint venture/real estate (in dollars per share)	$ 0.40	$ 0.03	$ 1.62
Net income from discontinued operations (in dollars per share)	$ 0.10	$ 0.07	$ 0.09
Gain on sale of discontinued operations (in dollars per share)	$ 0.07	$ 0.53	$ 0.44
Net income attributable to SL Green common stockholders (in dollars per share)	$ 1.74	$ 7.33	$ 3.45
Basic weighted average common shares outstanding (in shares)	89,319	83,762	78,101
Diluted weighted average common shares and common share equivalents outstanding (in shares)	92,873	86,244	79,761