XML 104 R89.htm IDEA: XBRL DOCUMENT
v3.25.2

Related Party Transactions (Details) - USD ($) $ in Thousands | 1 Months Ended | 3 Months Ended | 6 Months Ended | 12 Months Ended |
--- | --- | --- | --- | --- | ---
Jul. 31, 2024 | Dec. 31, 2016 | Jun. 30, 2025 | Jun. 30, 2024 | Jun. 30, 2025 | Jun. 30, 2024 | Dec. 31, 2022 | Dec. 31, 2024
Related Party Transactions |  |  |  |  |  |  |  |
Operating lease rent |  |  | $ 6,105 | $ 6,368 | $ 12,211 | $ 12,773 |  |
Rental revenue, net |  |  | 165,237 | 150,632 | 328,256 | 292,136 |  |
Related party receivables |  |  | 12,030 |  | 12,030 |  |  | $ 26,865
Due from joint venture |  |  |  |  |  |  |  |
Related Party Transactions |  |  |  |  |  |  |  |
Operating lease rent |  |  | 5,942 | 8,478 | 12,523 | 17,503 |  |
Related party receivables |  |  | 11,902 |  | 11,902 |  |  | 19,199
Other Affiliates |  |  |  |  |  |  |  |
Related Party Transactions |  |  |  |  |  |  |  |
Related party receivables |  |  | 128 |  | 128 |  |  | $ 7,666
One Vanderbilt Avenue |  |  |  |  |  |  |  |
Related Party Transactions |  |  |  |  |  |  |  |
Operating lease rent |  |  | 900 | 700 | 1,800 | 1,500 |  |
SUMMIT One Vanderbilt |  |  |  |  |  |  |  |
Related Party Transactions |  |  |  |  |  |  |  |
Operating lease rent |  |  | 6,300 | 6,300 | 12,600 | 12,600 |  |
Rental revenue, net |  |  | $ 3,500 | $ 4,100 | $ 7,000 | $ 8,300 |  |
Marc Holliday, Chairman And CEO | One Vanderbilt Avenue |  |  |  |  |  |  |  |
Related Party Transactions |  |  |  |  |  |  |  |
Stabilization of property, liquidation value, amount monetized |  | $ 1,400 |  |  |  |  |  |
Andrew Mathias, President | One Vanderbilt Avenue |  |  |  |  |  |  |  |
Related Party Transactions |  |  |  |  |  |  |  |
Stabilization of property, liquidation value, amount monetized |  | $ 1,000 |  |  |  |  |  |
Holiday And Mathias | Related party | One Vanderbilt Avenue |  |  |  |  |  |  |  |
Related Party Transactions |  |  |  |  |  |  |  |
Stabilization of property, anniversary period |  |  |  |  | 7 years |  |  |
Holiday And Mathias | One Vanderbilt Avenue | Related party |  |  |  |  |  |  |  |
Related Party Transactions |  |  |  |  |  |  |  |
Stabilization of property, within three years after stabilization, percent |  |  |  |  |  |  | 50.00% |
Stabilization period |  |  |  |  | 3 years |  |  |
Stabilization of property, three years or more after stabilization, percent |  |  |  |  | 100.00% |  |  |
Holliday | 760 Madison Avenue |  |  |  |  |  |  |  |
Related Party Transactions |  |  |  |  |  |  |  |
Proceeds from sale of property | $ 8,400 |  |  |  |  |  |  |
Minimum | Marc Holliday, Chairman And CEO | One Vanderbilt Avenue | Related party |  |  |  |  |  |  |  |
Related Party Transactions |  |  |  |  |  |  |  |
Percentage of profits due to investors (as a percentage) |  | 1.27% |  |  |  |  |  |
Minimum | Andrew Mathias, President | One Vanderbilt Avenue | Related party |  |  |  |  |  |  |  |
Related Party Transactions |  |  |  |  |  |  |  |
Percentage of profits due to investors (as a percentage) |  | 1.92% |  |  |  |  |  |
Maximum | Marc Holliday, Chairman And CEO | One Vanderbilt Avenue | Related party |  |  |  |  |  |  |  |
Related Party Transactions |  |  |  |  |  |  |  |
Percentage of profits due to investors (as a percentage) |  | 0.85% |  |  |  |  |  |
Maximum | Andrew Mathias, President | One Vanderbilt Avenue | Related party |  |  |  |  |  |  |  |
Related Party Transactions |  |  |  |  |  |  |  |
Percentage of profits due to investors (as a percentage) |  | 1.28% |  |  |  |  |  |

X
- Definition Related Party Transaction, Percentage of Profits Due to Investors + References No definition available. + Details
Name: | slg_RelatedPartyTransactionPercentageofProfitsDuetoInvestors
Namespace Prefix: | slg_
Data Type: | dtr-types:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Related Party Transaction, Stabilization Of Property, Anniversary Period + References No definition available. + Details
Name: | slg_RelatedPartyTransactionStabilizationOfPropertyAnniversaryPeriod
Namespace Prefix: | slg_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- Definition Related Party Transaction, Stabilization Of Property, Three Years Or More After Stabilization, Percent + References No definition available. + Details
Name: | slg_RelatedPartyTransactionStabilizationOfPropertyThreeYearsOrMoreAfterStabilizationPercent
Namespace Prefix: | slg_
Data Type: | dtr-types:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Related Party Transaction, Stabilization Of Property, Within Three Years After Stabilization, Percent + References No definition available. + Details
Name: | slg_RelatedPartyTransactionStabilizationOfPropertyWithinThreeYearsAfterStabilizationPercent
Namespace Prefix: | slg_
Data Type: | dtr-types:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Related Party Transaction, Stabilization Period + References No definition available. + Details
Name: | slg_RelatedPartyTransactionStabilizationPeriod
Namespace Prefix: | slg_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- Definition Amount of single lease cost, calculated by allocation of remaining cost of lease over remaining lease term. Includes, but is not limited to, single lease cost, after impairment of right-of-use asset, calculated by amortization of remaining right-of-use asset and accretion of lease liability. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Topic 842 -SubTopic 20 -Name Accounting Standards Codification -Section 55 -Paragraph 53 -Publisher FASB -URI https://asc.fasb.org/1943274/2147479589/842-20-55-53 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 842 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 4 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org/1943274/2147478964/842-20-50-4 + Details
Name: | us-gaap_OperatingLeaseCost
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Amount of operating lease income from lease payments and variable lease payments paid and payable to lessor. Includes, but is not limited to, variable lease payments not included in measurement of lease receivable. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 842 -SubTopic 30 -Name Accounting Standards Codification -Section 50 -Paragraph 5 -Publisher FASB -URI https://asc.fasb.org/1943274/2147479773/842-30-50-5 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 270 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 6A -Publisher FASB -URI https://asc.fasb.org/1943274/2147482964/270-10-50-6A Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Topic 842 -SubTopic 30 -Name Accounting Standards Codification -Section 45 -Paragraph 3 -Publisher FASB -URI https://asc.fasb.org/1943274/2147479016/842-30-45-3 + Details
Name: | us-gaap_OperatingLeaseLeaseIncome
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Amount due from parties in nontrade transactions, classified as other. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Topic 944 -SubTopic 605 -Name Accounting Standards Codification -Section 55 -Paragraph 14 -Publisher FASB -URI https://asc.fasb.org/1943274/2147477548/944-605-55-14 Reference 2: http://www.xbrl.org/2003/role/exampleRef -Topic 944 -SubTopic 605 -Name Accounting Standards Codification -Section 55 -Paragraph 11 -Publisher FASB -URI https://asc.fasb.org/1943274/2147477548/944-605-55-11 Reference 3: http://www.xbrl.org/2003/role/exampleRef -Topic 280 -SubTopic 10 -Name Accounting Standards Codification -Section 55 -Paragraph 49 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482785/280-10-55-49 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Topic 946 -SubTopic 210 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.6-04(5)(a)(5)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147479170/946-210-S99-1 Reference 5: http://www.xbrl.org/2003/role/disclosureRef -Topic 210 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(3)(a)(4)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1 Reference 6: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 944 -SubTopic 210 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03(a)(3)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147478777/944-210-S99-1 + Details
Name: | us-gaap_OtherReceivables
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Cash received for the sale of real estate that is not part of an investing activity during the current period. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 230 -SubTopic 10 -Name Accounting Standards Codification -Section 45 -Paragraph 12 -Subparagraph (c) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482740/230-10-45-12 + Details
Name: | us-gaap_ProceedsFromSaleOfRealEstate
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Amount of transactions with related party during the financial reporting period. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 850 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (c) -Publisher FASB -URI https://asc.fasb.org/1943274/2147483326/850-10-50-1 + Details
Name: | us-gaap_RelatedPartyTransactionAmountsOfTransaction
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition 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. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 850 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (d) -Publisher FASB -URI https://asc.fasb.org/1943274/2147483326/850-10-50-1 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 850 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (c) -Publisher FASB -URI https://asc.fasb.org/1943274/2147483326/850-10-50-1 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Topic 850 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 3 -Publisher FASB -URI https://asc.fasb.org/1943274/2147483326/850-10-50-3 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Topic 235 -SubTopic 10 -Name Accounting Standards Codification -Section S50 -Paragraph 1 -Publisher FASB -URI https://asc.fasb.org/1943274/2147480738/235-10-S50-1 Reference 5: http://www.xbrl.org/2003/role/disclosureRef -Topic 235 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.4-08(k)(2)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480678/235-10-S99-1 Reference 6: http://www.xbrl.org/2003/role/disclosureRef -Topic 235 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.4-08(k)(1)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480678/235-10-S99-1 Reference 7: http://www.xbrl.org/2003/role/disclosureRef -Topic 310 -SubTopic 10 -Name Accounting Standards Codification -Section 45 -Paragraph 13 -Publisher FASB -URI https://asc.fasb.org/1943274/2147481990/310-10-45-13 Reference 8: http://www.xbrl.org/2003/role/disclosureRef -Topic 946 -SubTopic 220 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.6-07(2)(c)(2)(i)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147479134/946-220-S99-1 Reference 9: http://www.xbrl.org/2003/role/disclosureRef -Topic 946 -SubTopic 220 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.6-07(2)(c)(2)(ii)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147479134/946-220-S99-1 Reference 10: http://www.xbrl.org/2003/role/disclosureRef -Topic 946 -SubTopic 220 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.6-07(2)(g)(3)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147479134/946-220-S99-1 + Details
Name: | us-gaap_RelatedPartyTransactionLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Details
Name: | us-gaap_RelatedPartyTransactionsByRelatedPartyAxis=us-gaap_CorporateJointVentureMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_RelatedPartyTransactionsByRelatedPartyAxis=us-gaap_OtherAffiliatesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis=slg_OneVanderbiltMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis=slg_SUMMITOneVanderbiltMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_CounterpartyNameAxis=slg_MarcHollidayChairmanAndCEOMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_CounterpartyNameAxis=slg_AndrewMathiasPresidentMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_CounterpartyNameAxis=slg_HolidayAndMathiasMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_RelatedPartyTransactionsByRelatedPartyAxis=us-gaap_RelatedPartyMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis=slg_OneVanderbiltMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_CounterpartyNameAxis=slg_HollidayMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis=slg_A760MadisonAvenueMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_RangeAxis=srt_MinimumMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_RangeAxis=srt_MaximumMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |