Consolidated Statement of Capital - USD ($) shares in Thousands, $ in Thousands	3 Months Ended	6 Months Ended	12 Months Ended
Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022	Dec. 31, 2022
Increase (Decrease) in Partner's Capital
DRSPP proceeds	$ 158	$ 110	$ 342	$ 199
Reallocation of noncontrolling interest in the Operating Partnership	(1,051)	37,938	(11,198)	(5,085)
Deferred compensation plan and stock awards, net of forfeitures and tax withholdings	7,445	8,475	15,004	13,531
Repurchases of common units				(151,197)
Contribution to consolidated joint venture interests	(112)	51,348	8,448	51,348
Cash distributions to noncontrolling interests	$ (627)	$ (2,897)	$ (763)	$ (3,020)
Common Stock
Increase (Decrease) in Partner's Capital
DRSPP proceeds (in shares)	7	2	12	3
Deferred compensation plan and stock awards, net of forfeitures and tax withholdings (in shares)	7	176	(5)	204
Deferred compensation plan and stock awards, net of forfeitures and tax withholdings		$ 2		$ 3
Repurchases of common units (in units)				(1,971)
Repurchases of common units				$ (20)
Noncontrolling Interests
Increase (Decrease) in Partner's Capital
Contribution to consolidated joint venture interests	(112)	51,348	$ 8,448	51,348
Cash distributions to noncontrolling interests	(627)	(2,897)	(763)	(3,020)
SL Green Operating Partnership
Increase (Decrease) in Partner's Capital
Beginning Balance	4,529,174	4,739,115	4,646,922	4,778,253	$ 4,778,253
Net loss	(357,497)	(36,735)	(395,115)	(25,389)
Other comprehensive income	38,341	15,856	8,165	55,353
Preferred distributions	(3,737)	(3,737)	(7,475)	(7,475)
DRSPP proceeds	158	110	342	199
Reallocation of noncontrolling interest in the Operating Partnership	(1,051)	37,938	(11,198)	(5,085)
Deferred compensation plan and stock awards, net of forfeitures and tax withholdings	7,445	8,475	15,004	13,531
Repurchases of common units				(151,197)
Contribution to consolidated joint venture interests	(112)	51,348	8,448	51,348
Cash distributions to noncontrolling interests	(627)	(2,897)	(763)	(3,020)
Issuance of special distribution paid primarily in units				160,620
Cash distributions declared	(52,261)	(60,709)	(104,497)	(118,374)
Ending Balance	4,159,833	4,748,764	4,159,833	4,748,764	4,646,922
SL Green Operating Partnership \| Series I Preferred Units \| Series I Preferred Stock
Increase (Decrease) in Partner's Capital
Beginning Balance	221,932	221,932	221,932	221,932	221,932
Ending Balance	221,932	221,932	221,932	221,932	221,932
SL Green Operating Partnership \| Common Stock \| Partners' Interest
Increase (Decrease) in Partner's Capital
Beginning Balance	$ 4,219,126	$ 4,511,333	$ 4,313,497	$ 4,589,702	$ 4,589,702
Beginning Balance (units)	64,373	64,124	64,380	64,105	64,105
Net loss	$ (356,457)	$ (40,139)	$ (392,450)	$ (28,650)
Preferred distributions	$ (3,737)	$ (3,737)	$ (7,475)	$ (7,475)
DRSPP proceeds (in shares)	7	2	12	3
DRSPP proceeds	$ 158	$ 110	$ 342	$ 199
Reallocation of noncontrolling interest in the Operating Partnership	$ (1,051)	$ 37,938	$ (11,198)	$ (5,085)
Deferred compensation plan and stock awards, net of forfeitures and tax withholdings (in shares)	7	176	(5)	204
Deferred compensation plan and stock awards, net of forfeitures and tax withholdings	$ 7,445	$ 8,475	$ 15,004	$ 13,531
Repurchases of common units (in units)				(1,971)
Repurchases of common units				$ (151,197)
Issuance of special distribution paid primarily in units (in shares)				1,961
Issuance of special distribution paid primarily in units				$ 160,620
Cash distributions declared	(52,261)	(60,709)	(104,497)	(118,374)
Ending Balance	$ 3,813,223	$ 4,453,271	$ 3,813,223	$ 4,453,271	$ 4,313,497
Ending Balance (units)	64,387	64,302	64,387	64,302	64,380
SL Green Operating Partnership \| Accumulated Other Comprehensive Loss
Increase (Decrease) in Partner's Capital
Beginning Balance	$ 19,428	$ (7,261)	$ 49,604	$ (46,758)	$ (46,758)
Other comprehensive income	38,341	15,856	8,165	55,353
Ending Balance	57,769	8,595	57,769	8,595	49,604
SL Green Operating Partnership \| Noncontrolling Interests
Increase (Decrease) in Partner's Capital
Beginning Balance	68,688	13,111	61,889	13,377	13,377
Net loss	(1,040)	3,404	(2,665)	3,261
Contribution to consolidated joint venture interests	(112)	51,348	8,448	51,348
Cash distributions to noncontrolling interests	(627)	(2,897)	(763)	(3,020)
Ending Balance	$ 66,909	$ 64,966	$ 66,909	$ 64,966	$ 61,889

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Total distributions to each class of partners (i.e., general, limited and preferred partners).

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