Noncontrolling Interests on the Company's Consolidated Financial Statements - Preferred Unit Activity (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2023	Dec. 31, 2022
Rollforward Analysis of Preferred Unit Activity
Redemption and conversion of common units		$ (29,817)
SL Green Operating Partnership
Rollforward Analysis of Preferred Unit Activity
Redemption and conversion of common units		(29,817)
SL Green Operating Partnership \| Preferred Units
Rollforward Analysis of Preferred Unit Activity
Balance at beginning of period	$ 177,943	196,075
Issuance of preferred units	0	0
Redemption and conversion of common units	(11,700)	(17,967)
Dividends paid on preferred units	(6,271)	(6,198)
Accrued dividends on preferred units	6,529	6,033
Balance at end of period	$ 166,501	$ 177,943

Noncontrolling Interest, Accrued Dividends On Preferred Units

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Noncontrolling Interest, Decrease From Distribution On Preferred Units

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Rollforward Analysis of Preferred Unit Activity [Roll Forward]

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Decrease in noncontrolling interest (for example, but not limited to, redeeming or purchasing the interests of noncontrolling shareholders, issuance of shares (interests) by the non-wholly owned subsidiary to the parent entity for other than cash, and a buyback of shares (interest) by the non-wholly owned subsidiary from the noncontrolling interests).

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Carrying amount of the equity interests owned by noncontrolling preferred unit holders in an entity included in the reporting entity's consolidated financial statements.

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Amount of increase in noncontrolling interest from subsidiary issuance of equity interests to noncontrolling interest holders.

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