Consolidated Statements of Comprehensive (Loss) Income - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Statement of Comprehensive Income [Abstract]
Net (loss) income	$ (96,921)	$ 30,222	$ (599,337)
Other comprehensive (loss) income:
(Decrease) increase in unrealized value of derivative instruments, including SL Green's share of joint venture derivative instruments	(43,829)	318	(32,437)
Increase (decrease) in unrealized value of marketable securities	631	552	(1,650)
Other comprehensive (loss) income	(43,198)	870	(34,087)
Comprehensive (loss) income	(140,119)	31,092	(633,424)
Net loss (income) attributable to noncontrolling interests and preferred units distributions	11	(8,212)	34,778
Other comprehensive loss (income) attributable to noncontrolling interests	2,804	(151)	1,960
Comprehensive income attributable to SL Green/SLGOP	$ (137,304)	$ 22,729	$ (596,686)