Accumulated Other Comprehensive Income (Loss), Gain (Loss) from Changes in Fair Value

No definition available.

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- Definition

The aggregate fair value of assets needed to immediately settle the derivative instruments with credit-risk-related contingent features if the credit-risk-related contingent features were triggered at the end of the reporting period.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 815
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 4H
-Subparagraph (f)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480434/815-10-50-4H

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- Definition

The estimated net amount of existing gains or losses on cash flow hedges at the reporting date expected to be reclassified to earnings within the next 12 months.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 815
-SubTopic 30
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480870/815-30-50-1

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- 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/2009/role/commonPracticeRef
-Topic 815
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 5A
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480434/815-10-50-5A

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 18
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481112/505-10-50-18

Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 815
-SubTopic 20
-Name Accounting Standards Codification
-Section 25
-Paragraph 6A
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480682/815-20-25-6A

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- Definition

The aggregate fair value amounts of derivative instruments that contain credit-risk-related contingent features that are in a net liability position at the end of the reporting period. For nonderivative instruments that are designated and qualify as hedging instruments, the fair value amounts are the carrying value of the nonderivative hedging instrument, including the adjustment for the foreign currency transaction gain (loss) on that instrument.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 815
-SubTopic 10
-Name Accounting Standards Codification
-Section 55
-Paragraph 185
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480401/815-10-55-185

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 815
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 4H
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480434/815-10-50-4H

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Financial Instruments: Derivatives and Hedging - Additional Information (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025
Financial Instruments: Derivatives and Hedging
Fair value of derivatives in a net liability position	$ 0.7		$ 0.7
Aggregate termination value	0.8		0.8
Income Statement Location [Axis]: us-gaap:IncomeLossFromEquityMethodInvestments
Financial Instruments: Derivatives and Hedging
Estimated current balance held in accumulated other comprehensive loss to be reclassified into earnings within the next 12 months			2.6
Income Statement Location [Axis]: us-gaap:InterestExpenseOther
Financial Instruments: Derivatives and Hedging
Gain (loss) from changes in fair value	1.0	$ 0.1	5.4	$ 0.1
Estimated current balance held in accumulated other comprehensive loss to be reclassified into earnings within the next 12 months			8.2
Interest Rate Cap \| Income Statement Location [Axis]: slg:GainLossOnPurchasePriceFairValueAdjustmentGross
Financial Instruments: Derivatives and Hedging
Gain (loss) from changes in fair value	0.1	$ (1.2)	3.2	$ (4.3)
Foreign Exchange Forward Contracts \| Income Statement Location [Axis]: slg:GainLossOnPurchasePriceFairValueAdjustmentGross
Financial Instruments: Derivatives and Hedging
Gain (loss) from changes in fair value	$ (0.6)		$ (0.7)