Consolidated Statements of Comprehensive (Loss) Income - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Statement of Comprehensive Income [Abstract]
Net loss	$ (379,228)	$ (37,949)	$ (417,585)	$ (24,464)
Other comprehensive income:
Increase in unrealized value of derivative instruments, including SL Green's share of joint venture derivative instruments	41,322	17,323	10,263	60,890
Decrease in unrealized value of marketable securities	(476)	(454)	(1,444)	(2,247)
Other comprehensive income	40,846	16,869	8,819	58,643
Comprehensive (loss) income	(338,382)	(21,080)	(408,766)	34,179
Net loss (income) attributable to noncontrolling interests and preferred units distributions	22,771	(2,190)	25,135	(4,186)
Other comprehensive income attributable to noncontrolling interests	(2,505)	(1,013)	(654)	(3,290)
Comprehensive (loss) income attributable to SL Green	$ (318,116)	$ (24,283)	$ (384,285)	$ 26,703