Consolidated Statements of Capital - USD ($) shares in Thousands, $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2026	Mar. 31, 2025	Dec. 31, 2025
Increase (Decrease) in Partner's Capital
DRSPP proceeds	$ 62	$ 75
Measurement adjustment for redeemable noncontrolling interest	(22,901)	(12,940)
Deferred compensation plan and unit awards, net of forfeitures and tax withholdings	1,670	(2,525)
Contributions to consolidated joint venture interests	40,399	3,437
Contributions to debt fund investments	81,725
Distributions from debt fund investments	(1,821)
Cash distributions to noncontrolling interests	$ (8,320)	$ (221)
Common Stock
Increase (Decrease) in Partner's Capital
DRSPP proceeds (in shares)	1	1
Conversion of common units (shares)	1	4
Deferred compensation plan and stock awards, net of forfeitures and tax withholdings (in units)	(37)	(86)
Deferred compensation plan and unit awards, net of forfeitures and tax withholdings		$ (1)
Noncontrolling Interests
Increase (Decrease) in Partner's Capital
Deferred compensation plan and unit awards, net of forfeitures and tax withholdings	$ 466
Contributions to consolidated joint venture interests	40,399	3,437
Contributions to debt fund investments	81,725
Distributions from debt fund investments	(1,821)
Cash distributions to noncontrolling interests	(8,320)	(221)
SL Green Operating Partnership
Increase (Decrease) in Partner's Capital
Beginning balance	3,912,448	4,069,951	$ 4,069,951
Net loss	(79,597)	(23,699)
Net (loss) income attributable to partnership units	6,678	1,465
Other comprehensive (loss) income	14,911	(23,038)
Perpetual preferred unit dividends	(3,738)	(3,738)
DRSPP proceeds	62	75
Measurement adjustment for redeemable noncontrolling interest	(22,901)	(12,940)
Deferred compensation plan and unit awards, net of forfeitures and tax withholdings	1,670	(2,525)
Proceeds from issuance of common stock		(871)
Contributions to consolidated joint venture interests	40,399	3,437
Contributions to debt fund investments	81,725
Distributions from debt fund investments	(1,821)
Cash distributions to noncontrolling interests	(8,320)	(221)
Cash distributions declared	(43,718)	(54,469)
Ending balance	3,897,798	3,953,427	3,912,448
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
Ending balance	221,932	221,932	221,932
SL Green Operating Partnership \| Common Stock \| Partners' Interest
Increase (Decrease) in Partner's Capital
Beginning balance	$ 3,471,421	$ 3,711,172	$ 3,711,172
Beginning balance (units)	71,159	71,097	71,097
Net loss	$ (87,331)	$ (18,802)
Net (loss) income attributable to partnership units	6,678	1,465
Perpetual preferred unit dividends	$ (3,738)	$ (3,738)
DRSPP proceeds (in shares)	1	1
DRSPP proceeds	$ 62	$ 75
Conversion of common units (shares)	1	4
Measurement adjustment for redeemable noncontrolling interest	$ (22,901)	$ (12,940)
Deferred compensation plan and stock awards, net of forfeitures and tax withholdings (in units)	(37)	(86)
Deferred compensation plan and unit awards, net of forfeitures and tax withholdings	$ 1,204	$ (2,525)
Proceeds from issuance of common stock		(871)
Cash distributions declared	(43,718)	(54,469)
Ending balance	$ 3,321,677	$ 3,619,367	$ 3,471,421
Ending balance (units)	71,124	71,016	71,159
SL Green Operating Partnership \| Accumulated Other Comprehensive Income (Loss)
Increase (Decrease) in Partner's Capital
Beginning balance	$ (22,198)	$ 18,196	$ 18,196
Other comprehensive (loss) income	14,911	(23,038)
Ending balance	(7,287)	(4,842)	(22,198)
SL Green Operating Partnership \| Noncontrolling Interests
Increase (Decrease) in Partner's Capital
Beginning balance	241,293	118,651	118,651
Net loss	7,734	(4,897)
Deferred compensation plan and unit awards, net of forfeitures and tax withholdings	466
Contributions to consolidated joint venture interests	40,399	3,437
Contributions to debt fund investments	81,725
Distributions from debt fund investments	(1,821)
Cash distributions to noncontrolling interests	(8,320)	(221)
Ending balance	$ 361,476	$ 116,970	$ 241,293

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Other Comprehensive Income (Loss), Net of Tax, Less Portion Attributable to Noncontrolling Interest

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The consolidated profit or loss for the period, net of income taxes, including the portion attributable to the noncontrolling interest, less preferred distributions during the period.

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Decrease in noncontrolling interest balance from payment of dividends or other distributions by the non-wholly owned subsidiary or partially owned entity, included in the consolidation of the parent entity, to the noncontrolling interest holders.

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Amount of income (loss) from consolidated real estate investments attributed to parent.

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The number of shares issued during the period upon the conversion of units. An example of a convertible unit is an umbrella partnership real estate investment trust unit (UPREIT unit).

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