Consolidated Statements of Comprehensive Income (Loss) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
Statement of Comprehensive Income [Abstract]
Net income (loss)	$ 1,959	$ (379,228)	$ 20,348	$ (417,585)
Other comprehensive income:
(Decrease) increase in unrealized value of derivative instruments, including SL Green's share of joint venture derivative instruments	(98)	41,322	23,116	10,263
Increase (decrease) in unrealized value of marketable securities	316	(476)	1,398	(1,444)
Other comprehensive income	218	40,846	24,514	8,819
Comprehensive income (loss)	2,177	(338,382)	44,862	(408,766)
Net (income) loss attributable to noncontrolling interests and preferred units distributions	(382)	22,771	(1,892)	25,135
Other comprehensive loss (income) attributable to noncontrolling interests	2	(2,505)	(1,620)	(654)
Comprehensive income (loss) attributable to SL Green	$ 1,797	$ (318,116)	$ 41,350	$ (384,285)