v3.25.3

Cover	Oct. 31, 2025
Entity Information [Line Items]
Document Type	8-K
Amendment Flag	false
Document Period End Date	Oct. 31, 2025
Entity File Number	1-13199
Entity Registrant Name	SL GREEN REALTY CORP.
Entity Central Index Key	0001040971
Entity Tax Identification Number	13-3956775
Entity Incorporation, State or Country Code	MD
Entity Address, Address Line One	One Vanderbilt Avenue
Entity Address, City or Town	New York
Entity Address, State or Province	NY
Entity Address, Postal Zip Code	10017
City Area Code	212
Local Phone Number	594-2700
Written Communications	false
Soliciting Material	false
Pre-commencement Tender Offer	false
Pre-commencement Issuer Tender Offer	false
Entity Emerging Growth Company	false
Common Stock
Entity Information [Line Items]
Title of 12(b) Security	Common Stock, $0.01 par value
Trading Symbol	SLG
Security Exchange Name	NYSE
Series I Preferred Stock [Member]
Entity Information [Line Items]
Title of 12(b) Security	6.500% Series I Cumulative Redeemable Preferred Stock, $0.01 par value
Trading Symbol	SLG.PRI
Security Exchange Name	NYSE
S L Green Operating Partnership L P [Member]
Entity Information [Line Items]
Document Type	8-K
Amendment Flag	false
Entity File Number	333-167793-02
Entity Registrant Name	SL GREEN OPERATING PARTNERSHIP, L.P.
Entity Central Index Key	0001492869
Entity Tax Identification Number	13-3960398
Entity Incorporation, State or Country Code	DE
Entity Address, Address Line One	One Vanderbilt Avenue
Entity Address, City or Town	New York
Entity Address, State or Province	NY
Entity Address, Postal Zip Code	10017
City Area Code	212
Local Phone Number	594-2700
Written Communications	false
Soliciting Material	false
Pre-commencement Tender Offer	false
Pre-commencement Issuer Tender Offer	false
Entity Emerging Growth Company	false

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Area code of city

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For the EDGAR submission types of Form 8-K: the date of the report, the date of the earliest event reported; for the EDGAR submission types of Form N-1A: the filing date; for all other submission types: the end of the reporting or transition period. The format of the date is YYYY-MM-DD.

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The type of document being provided (such as 10-K, 10-Q, 485BPOS, etc). The document type is limited to the same value as the supporting SEC submission type, or the word 'Other'.

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Address Line 1 such as Attn, Building Name, Street Name

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Name of the City or Town

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Name of the state or province.

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A unique 10-digit SEC-issued value to identify entities that have filed disclosures with the SEC. It is commonly abbreviated as CIK.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Commission file number. The field allows up to 17 characters. The prefix may contain 1-3 digits, the sequence number may contain 1-8 digits, the optional suffix may contain 1-4 characters, and the fields are separated with a hyphen.

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Two-character EDGAR code representing the state or country of incorporation.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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The exact name of the entity filing the report as specified in its charter, which is required by forms filed with the SEC.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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The Tax Identification Number (TIN), also known as an Employer Identification Number (EIN), is a unique 9-digit value assigned by the IRS.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Local phone number for entity.

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Boolean flag that is true when the Form 8-K filing is intended to satisfy the filing obligation of the registrant as pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Boolean flag that is true when the Form 8-K filing is intended to satisfy the filing obligation of the registrant as pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Boolean flag that is true when the Form 8-K filing is intended to satisfy the filing obligation of the registrant as soliciting material pursuant to Rule 14a-12 under the Exchange Act.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Trading symbol of an instrument as listed on an exchange.

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Boolean flag that is true when the Form 8-K filing is intended to satisfy the filing obligation of the registrant as written communications pursuant to Rule 425 under the Securities Act.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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SL GREEN REALTY CORP 8-K