Noncontrolling Interests on the Company's Consolidated Financial Statements - Common Unit Activity (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended	12 Months Ended
Sep. 30, 2022	Sep. 30, 2022	Dec. 31, 2021
Rollforward Analysis of Preferred Unit Activity
Redemption of preferred units	$ (29,817)	$ (29,817)
SL Green Operating Partnership
Rollforward Analysis of Preferred Unit Activity
Redemption of preferred units	(29,817)	(29,817)
SL Green Operating Partnership \| Series I Preferred Units
Rollforward Analysis of Preferred Unit Activity
Balance at beginning of period		196,075	$ 202,169
Issuance of preferred units		0	0
Redemption of preferred units		(17,967)	(6,040)
Dividends paid on preferred units		(4,749)	(6,760)
Accrued dividends on preferred units		4,584	6,706
Balance at end of period	$ 177,943	$ 177,943	$ 196,075

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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