XML 137 R117.htm IDEA: XBRL DOCUMENT
v3.24.0.1

Financial Instruments: Derivatives and Hedging - Schedule of Notional and Fair Value of Derivative Financial Instruments and Foreign Currency Hedges (Details) - USD ($) $ in Thousands | Dec. 31, 2023 | Dec. 31, 2022
--- | --- | ---
Financial Instruments: Derivatives and Hedging |  |
Fair Value | $ 33,456 | $ 57,660
Interest Rate Swaps/Caps |  |
Financial Instruments: Derivatives and Hedging |  |
Fair Value | 16,348 |
Interest Rate Swaps/Caps | Due from joint ventures |  |
Financial Instruments: Derivatives and Hedging |  |
Fair Value | 43,034 |
Interest Rate Swap Expiring January 2024 |  |
Financial Instruments: Derivatives and Hedging |  |
Notional Value | $ 150,000 |
Strike Rate | 2.60% |
Fair Value | $ 11 |
Interest Rate Swap Expiring in January 2024, 2 |  |
Financial Instruments: Derivatives and Hedging |  |
Notional Value | $ 200,000 |
Strike Rate | 4.49% |
Fair Value | $ 5 |
Interest Rate Swap Expiring in January 2024, 3 |  |
Financial Instruments: Derivatives and Hedging |  |
Notional Value | $ 200,000 |
Strike Rate | 4.411% |
Fair Value | $ 5 |
Interest Rate Cap Expiring June 2024 |  |
Financial Instruments: Derivatives and Hedging |  |
Notional Value | $ 370,000 |
Strike Rate | 3.25% |
Fair Value | $ 3,158 |
Interest Rate Cap Expiring June 2024 | Due from joint ventures |  |
Financial Instruments: Derivatives and Hedging |  |
Notional Value | $ 505,412 |
Strike Rate | 3.00% |
Fair Value | $ 4,948 |
Interest Rate Cap Expiring in June 2024, 2 |  |
Financial Instruments: Derivatives and Hedging |  |
Notional Value | $ 370,000 |
Strike Rate | 3.25% |
Fair Value | $ (3,145) |
Interest Rate Swap Expiring January 2026 |  |
Financial Instruments: Derivatives and Hedging |  |
Notional Value | $ 150,000 |
Strike Rate | 2.621% |
Fair Value | $ 4,011 |
Interest Rate Swap Expiring January 2026, 2 |  |
Financial Instruments: Derivatives and Hedging |  |
Notional Value | $ 200,000 |
Strike Rate | 2.662% |
Fair Value | $ 5,196 |
Interest Rate Swap Expiring in February 2027 |  |
Financial Instruments: Derivatives and Hedging |  |
Notional Value | $ 100,000 |
Strike Rate | 2.903% |
Fair Value | $ 2,281 |
Interest Rate Swap Expiring in February 2027, 2 |  |
Financial Instruments: Derivatives and Hedging |  |
Notional Value | $ 100,000 |
Strike Rate | 2.733% |
Fair Value | $ 2,775 |
Interest Rate Swap Expiring in February 2027, 3 |  |
Financial Instruments: Derivatives and Hedging |  |
Notional Value | $ 50,000 |
Strike Rate | 2.463% |
Fair Value | $ 1,781 |
Interest Rate Swap Expiring in February 2027, 4 |  |
Financial Instruments: Derivatives and Hedging |  |
Notional Value | $ 200,000 |
Strike Rate | 2.591% |
Fair Value | $ 6,378 |
Interest Rate Swap Expiring in May 2027 |  |
Financial Instruments: Derivatives and Hedging |  |
Notional Value | $ 300,000 |
Strike Rate | 2.866% |
Fair Value | $ 7,306 |
Interest Rate Swap Expiring in May 2027, 2 |  |
Financial Instruments: Derivatives and Hedging |  |
Notional Value | $ 150,000 |
Strike Rate | 3.524% |
Fair Value | $ 549 |
Interest Rate Swap Expiring in June 2027 |  |
Financial Instruments: Derivatives and Hedging |  |
Notional Value | $ 370,000 |
Strike Rate | 3.888% |
Fair Value | $ (3,044) |
Interest Rate Swap Expiring in November 2027 |  |
Financial Instruments: Derivatives and Hedging |  |
Notional Value | $ 300,000 |
Strike Rate | 4.487% |
Fair Value | $ (10,273) |
Interest Rate Swap Expiring in January 2028 |  |
Financial Instruments: Derivatives and Hedging |  |
Notional Value | $ 100,000 |
Strike Rate | 3.756% |
Fair Value | $ (646) |
Interest Rate Cap Expiring February 2024 | Due from joint ventures |  |
Financial Instruments: Derivatives and Hedging |  |
Notional Value | $ 220,000 |
Strike Rate | 4.00% |
Fair Value | $ 318 |
Interest Rate Cap Expiring May 2024 | Due from joint ventures |  |
Financial Instruments: Derivatives and Hedging |  |
Notional Value | $ 484,069 |
Strike Rate | 0.49% |
Fair Value | $ 8,331 |
Interest Rate Cap Expiring May 2024, 2 | Due from joint ventures |  |
Financial Instruments: Derivatives and Hedging |  |
Notional Value | $ 484,069 |
Strike Rate | 0.49% |
Fair Value | $ 8,330 |
Interest Rate Cap Expiring August 2024 | Due from joint ventures |  |
Financial Instruments: Derivatives and Hedging |  |
Notional Value | $ 272,000 |
Strike Rate | 4.00% |
Fair Value | $ 1,675 |
Interest Rate Cap Expiring September 2024 | Due from joint ventures |  |
Financial Instruments: Derivatives and Hedging |  |
Notional Value | $ 477,783 |
Strike Rate | 3.50% |
Fair Value | $ 5,213 |
Interest Rate Cap Expiring November 2024 | Due from joint ventures |  |
Financial Instruments: Derivatives and Hedging |  |
Notional Value | $ 278,161 |
Strike Rate | 4.00% |
Fair Value | $ 948 |
Interest Rate Cap Expiring November 2024, 2 | Due from joint ventures |  |
Financial Instruments: Derivatives and Hedging |  |
Notional Value | $ 278,161 |
Strike Rate | 4.00% |
Fair Value | $ 948 |
Interest Rate Swap Expiring February 2026 | Due from joint ventures |  |
Financial Instruments: Derivatives and Hedging |  |
Notional Value | $ 250,000 |
Strike Rate | 3.608% |
Fair Value | $ 1,819 |
Interest Rate Swap Expiring February 2026, 2 | Due from joint ventures |  |
Financial Instruments: Derivatives and Hedging |  |
Notional Value | $ 250,000 |
Strike Rate | 3.608% |
Fair Value | $ 1,818 |
Interest Rate Swap Expiring February 2026, 3 | Due from joint ventures |  |
Financial Instruments: Derivatives and Hedging |  |
Notional Value | $ 177,000 |
Strike Rate | 1.555% |
Fair Value | $ 8,686 |

X
- Definition Nominal or face amount used to calculate payments on the derivative asset. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 946 -SubTopic 320 -Name Accounting Standards Codification -Section S99 -Paragraph 5 -Subparagraph (SX 210.12-13(Column A)(Footnote 3)) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480032/946-320-S99-5 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 946 -SubTopic 320 -Name Accounting Standards Codification -Section S99 -Paragraph 5C -Subparagraph (SX 210.12-13C(Column E)) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480032/946-320-S99-5C Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Topic 946 -SubTopic 320 -Name Accounting Standards Codification -Section S99 -Paragraph 5A -Subparagraph (SX 210.12-13A(Column D)) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480032/946-320-S99-5A Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Topic 946 -SubTopic 320 -Name Accounting Standards Codification -Section S99 -Paragraph 5B -Subparagraph (SX 210.12-13B(Column B)) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480032/946-320-S99-5B Reference 5: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 815 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 1B -Publisher FASB -URI https://asc.fasb.org//1943274/2147480434/815-10-50-1B Reference 6: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 815 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 1A -Subparagraph (d) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480434/815-10-50-1A Reference 7: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 815 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 1A -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480434/815-10-50-1A + Details
Name: | us-gaap_DerivativeAssetNotionalAmount
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | na
Period Type: | instant

X
- Definition Fair value, before effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets elected not to be offset. Excludes assets not subject to a master netting arrangement. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Topic 210 -SubTopic 20 -Name Accounting Standards Codification -Section 55 -Paragraph 22 -Publisher FASB -URI https://asc.fasb.org//1943274/2147483444/210-20-55-22 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 210 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 3 -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org//1943274/2147483466/210-20-50-3 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 210 -SubTopic 20 -Name Accounting Standards Codification -Section 55 -Paragraph 7 -Publisher FASB -URI https://asc.fasb.org//1943274/2147483444/210-20-55-7 Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4B -Subparagraph (a),(c) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480434/815-10-50-4B Reference 5: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Section 50 -Paragraph 4D -Subparagraph (c)(2) -SubTopic 20 -Topic 860 -Publisher FASB -URI https://asc.fasb.org//1943274/2147481326/860-20-50-4D + Details
Name: | us-gaap_DerivativeFairValueOfDerivativeAsset
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Fixed interest rate related to the interest rate derivative. + References No definition available. + Details
Name: | us-gaap_DerivativeFixedInterestRate
Namespace Prefix: | us-gaap_
Data Type: | dtr-types:percentItemType
Balance Type: | na
Period Type: | instant

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 815 -SubTopic 40 -Name Accounting Standards Codification -Section 50 -Paragraph 5 -Subparagraph (f) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480237/815-40-50-5 + Details
Name: | us-gaap_DerivativeLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Details
Name: | us-gaap_DerivativeInstrumentRiskAxis=us-gaap_InterestRateContractMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

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

X
- Details
Name: | us-gaap_DerivativeInstrumentRiskAxis=slg_InterestRateSwapExpiringJanuary2024Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DerivativeInstrumentRiskAxis=slg_InterestRateSwapExpiringInJanuary20242Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DerivativeInstrumentRiskAxis=slg_InterestRateSwapExpiringInJanuary20243Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DerivativeInstrumentRiskAxis=slg_InterestRateCapExpiringJune2024Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DerivativeInstrumentRiskAxis=slg_InterestRateCapExpiringInJune20242Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DerivativeInstrumentRiskAxis=slg_InterestRateSwapExpiringJanuary2026Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DerivativeInstrumentRiskAxis=slg_InterestRateSwapExpiringJanuary20262Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DerivativeInstrumentRiskAxis=slg_InterestRateSwapExpiringInFebruary2027Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DerivativeInstrumentRiskAxis=slg_InterestRateSwapExpiringInFebruary20272Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DerivativeInstrumentRiskAxis=slg_InterestRateSwapExpiringInFebruary20273Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DerivativeInstrumentRiskAxis=slg_InterestRateSwapExpiringInFebruary20274Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DerivativeInstrumentRiskAxis=slg_InterestRateSwapExpiringInMay2027Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DerivativeInstrumentRiskAxis=slg_InterestRateSwapExpiringInMay20272Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DerivativeInstrumentRiskAxis=slg_InterestRateSwapExpiringInJune2027Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DerivativeInstrumentRiskAxis=slg_InterestRateSwapExpiringInNovember2027Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DerivativeInstrumentRiskAxis=slg_InterestRateSwapExpiringInJanuary2028Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DerivativeInstrumentRiskAxis=slg_InterestRateCapExpiringFebruary2024Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DerivativeInstrumentRiskAxis=slg_InterestRateCapExpiringMay2024Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DerivativeInstrumentRiskAxis=slg_InterestRateCapExpiringMay20242Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DerivativeInstrumentRiskAxis=slg_InterestRateCapExpiringAugust2024Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DerivativeInstrumentRiskAxis=slg_InterestRateCapExpiringSeptember2024Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DerivativeInstrumentRiskAxis=slg_InterestRateCapExpiringNovember2024Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DerivativeInstrumentRiskAxis=slg_InterestRateCapExpiringNovember20242Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DerivativeInstrumentRiskAxis=slg_InterestRateSwapExpiringFebruary2026Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DerivativeInstrumentRiskAxis=slg_InterestRateSwapExpiringFebruary20262Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DerivativeInstrumentRiskAxis=slg_InterestRateSwapExpiringFebruary20263Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |