Consolidated Statements of Capital - USD ($) shares in Thousands, $ in Thousands	12 Months Ended
Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Increase (Decrease) in Partner's Capital
Acquisition of subsidiary interest from noncontrolling interest		$ (29,817)
DRSPP proceeds	$ 525	525	$ 738
Reallocation of noncontrolling interest in the Operating Partnership	(15,486)	39,974	(9,851)
Deferred compensation plan and stock awards, net of forfeitures and tax withholdings	35,573	32,034	32,583
Repurchases of common units		(151,197)	(337,624)
Contributions to consolidated joint venture interests	15,066	52,164	336
Sale of interest in partially owned entity			(4,476)
Cash distributions to noncontrolling interests	$ (2,777)	$ (4,699)	$ (6,631)
Common Stock
Increase (Decrease) in Partner's Capital
DRSPP proceeds (in units)	17	11	11
Deferred compensation plan and stock awards, net of forfeitures and tax withholdings (in units)	329	274	108
Deferred compensation plan and stock awards, net of forfeitures and tax withholdings	$ 4	$ 4	$ 2
Repurchases of common units (in units)		(1,971)	(4,474)
Repurchases of common units		$ (20)	$ (46)
Noncontrolling Interests
Increase (Decrease) in Partner's Capital
Acquisition of subsidiary interest from noncontrolling interest		(75)
Contributions to consolidated joint venture interests	15,066	52,164	336
Sale of interest in partially owned entity			(4,476)
Cash distributions to noncontrolling interests	(2,777)	(4,699)	(6,631)
SL Green Operating Partnership
Increase (Decrease) in Partner's Capital
Beginning balance	4,646,922	4,778,253	4,935,795
Net income (loss)	(569,127)	(76,952)	447,870
Acquisition of subsidiary interest from noncontrolling interest		(29,817)
Other comprehensive income (loss)	(32,127)	96,362	20,489
Perpetual preferred unit dividends	(14,950)	(14,950)	(14,950)
DRSPP proceeds	525	525	738
Reallocation of noncontrolling interest in the Operating Partnership	(15,486)	39,974	(9,851)
Deferred compensation plan and stock awards, net of forfeitures and tax withholdings	35,573	32,034	32,583
Repurchases of common units		(151,197)	(337,624)
Proceeds from stock options exercised			818
Contributions to consolidated joint venture interests	15,066	52,164	336
Cash distributions to noncontrolling interests	(2,777)	(4,699)	(6,631)
Issuance of special distribution paid in units		160,620	123,529
Cash distributions declared	(207,694)	(235,395)	(410,373)
Ending balance	3,855,925	4,646,922	4,778,253
SL Green Operating Partnership \| Preferred Units \| Series I Preferred Units
Increase (Decrease) in Partner's Capital
Beginning balance	221,932	221,932	221,932
Ending balance	221,932	221,932	221,932
SL Green Operating Partnership \| Common Stock \| Partners' Interest
Increase (Decrease) in Partner's Capital
Beginning balance	$ 4,313,497	$ 4,589,702	$ 4,755,078
Beginning balance (units)	64,380	64,105	66,474
Net income (loss)	$ (564,559)	$ (78,074)	$ 449,754
Acquisition of subsidiary interest from noncontrolling interest		(29,742)
Perpetual preferred unit dividends	$ (14,950)	$ (14,950)	$ (14,950)
DRSPP proceeds (in units)	17	11	11
DRSPP proceeds	$ 525	$ 525	$ 738
Reallocation of noncontrolling interest in the Operating Partnership	$ (15,486)	$ 39,974	$ (9,851)
Deferred compensation plan and stock awards, net of forfeitures and tax withholdings (in units)	329	274	108
Deferred compensation plan and stock awards, net of forfeitures and tax withholdings	$ 35,573	$ 32,034	$ 32,583
Repurchases of common units (in units)		(1,971)	(4,474)
Repurchases of common units		$ (151,197)	$ (337,624)
Proceeds from stock options exercised (in units)			12
Proceeds from stock options exercised			$ 818
Issuance of special distribution paid in units (in shares)		1,961	1,974
Issuance of special distribution paid in units		$ 160,620	$ 123,529
Cash distributions declared	(207,694)	(235,395)	(410,373)
Ending balance	$ 3,546,906	$ 4,313,497	$ 4,589,702
Ending balance (units)	64,726	64,380	64,105
SL Green Operating Partnership \| Accumulated Other Comprehensive (Loss) Income
Increase (Decrease) in Partner's Capital
Beginning balance	$ 49,604	$ (46,758)	$ (67,247)
Other comprehensive income (loss)	(32,127)	96,362	20,489
Ending balance	17,477	49,604	(46,758)
SL Green Operating Partnership \| Noncontrolling Interests
Increase (Decrease) in Partner's Capital
Beginning balance	61,889	13,377	26,032
Net income (loss)	(4,568)	1,122	(1,884)
Acquisition of subsidiary interest from noncontrolling interest		(75)
Contributions to consolidated joint venture interests	15,066	52,164	336
Sale of interest in partially owned entity			(4,476)
Cash distributions to noncontrolling interests	(2,777)	(4,699)	(6,631)
Ending balance	$ 69,610	$ 61,889	$ 13,377

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