Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Mar. 31, 2017	Dec. 31, 2016
Preferred stock, par value (in dollars per share)	$ 0.01
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, shares authorized (in shares)	160,000,000	160,000,000
Common stock, shares issued (in shares)	101,831,000	101,617,000
Common stock, shares outstanding (in shares)	101,831,000	101,617,000
Treasury stock, shares (in shares)	1,055,000	1,055,000
Series I Preferred Stock
Preferred stock, par value (in dollars per share)	$ 0.01	$ 0.01
Preferred stock, liquidation preference (in dollars per share)	$ 25	$ 25.00
Preferred stock, shares issued (in shares)	9,200,000	9,200,000
Preferred stock, shares outstanding (in shares)	9,200,000	9,200,000
SL Green Operating Partnership
Tenant and other receivables, allowance	$ 16,634	$ 16,592
Deferred rents receivable, allowance	24,079	25,203
Debt and preferred equity investments, discount and deferred origination fees	$ 16,316	$ 16,705
Limited partner interests in Operating Partnership, limited partner common units outstanding (shares)	4,563,000	4,364,000
SL Green partner's capital, general partner common units outstanding (shares)	1,053,000	1,049,000
SL Green partners' capital, limited partner common units outstanding (shares)	99,723,000	99,513,000
SL Green Operating Partnership | Series I Preferred Stock
Preferred units, liquidation preference (in dollars per share)	$ 25.00	$ 25.00
Preferred units, shares issued	9,200,000	9,200,000
Preferred units, shares outstanding	9,200,000	9,200,000