Common Units Redemption, Period Of Restriction

No definition available.

Name:	slg_CommonUnitsRedemptionPeriodOfRestriction
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Balance Type:	na
Period Type:	duration

- Definition

Represents the number of partnership units owned by the noncontrolling unit holders.

+ References

No definition available.

+ Details

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Balance Type:	na
Period Type:	instant

- Definition

-- None. No documentation exists for this element. --

+ References

No definition available.

+ Details

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- Definition

Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 260
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-Paragraph 1
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-Publisher FASB
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Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

- Definition

The number of new shares issued in the conversion of stock in a noncash (or part noncash) transaction. Noncash is defined as transactions during a period that do not result in cash receipts or cash payments in the period. "Part noncash" refers to that portion of the transaction not resulting in cash receipts or cash payments in the period.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 230
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-Publisher FASB
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Balance Type:	na
Period Type:	duration

- Definition

The equity interest of noncontrolling shareholders, partners or other equity holders in consolidated entity.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
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Period Type:	instant

- Definition

Aggregate share number for all nonredeemable preferred stock (or preferred stock redeemable solely at the option of the issuer) held by stockholders. Does not include preferred shares that have been repurchased.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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+ Details

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Balance Type:	na
Period Type:	instant

- Definition

Number of shares of stock issued as of the balance sheet date, including shares that had been issued and were previously outstanding but which are now held in the treasury.

+ References

No definition available.

+ Details

Name:	us-gaap_SharesIssued
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Balance Type:	na
Period Type:	instant

- Definition

Number of shares issued which are neither cancelled nor held in the treasury.

+ References

+ Details

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Partners' Capital of the Operating Partnership - Additional Information (Details) - shares	3 Months Ended		6 Months Ended
	Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025	Dec. 31, 2025
Stockholders' Equity
Common stock shares excluded from the diluted shares outstanding (in shares)	7,056,832	352,917	7,259,653	352,917
Series I Preferred Units
Stockholders' Equity
Preferred stock, shares outstanding (in shares)	9,200,000		9,200,000		9,200,000
SL Green Operating Partnership
Stockholders' Equity
Shares, issued (in shares)	70,852,556		70,852,556
Units outstanding (units)	70,852,556		70,852,556
Number of units of operating partnership owned by the noncontrolling interest unit holders (units)	5,547,004		5,547,004		4,877,891
Common stock shares excluded from the diluted shares outstanding (in shares)	2,200,650	352,917	2,341,909	352,917
SL Green Operating Partnership \| Operating Partnership
Stockholders' Equity
Noncontrolling interest in the operating partnership (as a percent)	7.26%		7.26%		6.42%
SL Green Operating Partnership \| Series I Preferred Units
Stockholders' Equity
Period of restriction to redeem OP Units			1 year
Conversion of stock, shares issued			1