Stockholders' Equity of the Company - Additional Information (Details) - $ / shares	Sep. 30, 2023	Jun. 30, 2023	Dec. 31, 2022	Sep. 30, 2022	Jun. 30, 2022	Dec. 31, 2021
Equity, Class of Treasury Stock [Line Items]
Authorized capital stock (shares)	260,000,000
Authorized shares, par value (in dollars per share)	$ 0.01
Common stock, shares authorized (in shares)	160,000,000		160,000,000
Common stock, par value (in dollars per share)	$ 0.01		$ 0.01
Excess stock, shares authorized (shares)	75,000,000
Excess stock, par value (in dollars per share)	$ 0.01
Preferred stock, shares authorized (shares)	25,000,000
Preferred stock, par value (in dollars per share)	$ 0.01
Excess shares issued (shares)	0
Excess shares outstanding (in shares)	0
Common Stock
Equity, Class of Treasury Stock [Line Items]
Shares, outstanding (in shares)	64,398,000	64,387,000	64,380,000	64,316,000	64,302,000	64,105,000
SL Green Operating Partnership | Common Stock
Equity, Class of Treasury Stock [Line Items]
Shares, outstanding (in shares)	64,397,983
Shares, issued (in shares)	64,397,983