Mortgage Loans on Real Estate, Senior Financing

No definition available.

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Namespace Prefix:	slg_
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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

No definition available.

+ Details

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- Definition

Weighted average interest rate of debt outstanding.

+ References

No definition available.

+ Details

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Period Type:	instant

- Definition

Rate of interest on investment.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=121645371&loc=d3e27232-111563

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=121645371&loc=d3e27161-111563

+ Details

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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Nominal or face amount on the investment owned.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 20
-Section 10
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6438156&loc=d3e57880-113973

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 10
-Paragraph 1
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=6431724&loc=d3e32938-113948

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

The percentage points (also referred to as 'margin') added to the reference rate as stated in the loan agreement and used to compute the variable rate on the loans receivable. For instance, the loan agreement might state that the interest rate the borrower is obligated to pay is the London Interbank Offered Rate (LIBOR) plus three quarters (3/4) of a percentage point adjusted quarterly (each three months). LIBOR in this example is the index or reference rate, 3/4 percentage point is the margin, the reference rate plus the margin is the fully indexed rate. This element would be used to report separately the margin.

+ References

No definition available.

+ Details

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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

The balance represents the amount of loans that are secured by real estate mortgages, offset by the reserve to cover probable credit losses on the loan portfolio.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03.1(c))
-URI http://asc.fasb.org/extlink&oid=120400017&loc=d3e572229-122910

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Debt and Preferred Equity Investments - Debt and Preferred Equity Investments (Details) - USD ($) $ in Thousands	Jun. 30, 2021	Dec. 31, 2020
Debt Instrument [Line Items]
Carrying Value	$ 1,072,711	$ 1,076,542
Senior Financing	6,760,192
Total floating rate
Debt Instrument [Line Items]
Carrying Value	308,351
Face Value	316,837
Total fixed rate
Debt Instrument [Line Items]
Carrying Value	764,360
Face Value	777,008
Senior Mortgage Debt
Debt Instrument [Line Items]
Carrying Value	15,003
Senior Financing	$ 0
Weighted Average Yield at End of Period	5.33%
Senior Mortgage Debt \| Total floating rate
Debt Instrument [Line Items]
Carrying Value	$ 13,753
Face Value	14,048
Senior Mortgage Debt \| Total fixed rate
Debt Instrument [Line Items]
Carrying Value	1,250
Face Value	1,250
Junior Mortgage Debt
Debt Instrument [Line Items]
Carrying Value	7,213
Senior Financing	$ 60,000
Weighted Average Yield at End of Period	7.54%
Junior Mortgage Debt \| Total floating rate
Debt Instrument [Line Items]
Carrying Value	$ 7,213
Face Value	12,000
Junior Mortgage Debt \| Total fixed rate
Debt Instrument [Line Items]
Carrying Value	0
Face Value	0
Mezzanine Debt
Debt Instrument [Line Items]
Carrying Value	784,240
Senior Financing	$ 4,737,442
Weighted Average Yield at End of Period	6.51%
Mezzanine Debt \| Total floating rate
Debt Instrument [Line Items]
Carrying Value	$ 287,385
Face Value	290,789
Mezzanine Debt \| Total fixed rate
Debt Instrument [Line Items]
Carrying Value	496,855
Face Value	507,842
Preferred Equity
Debt Instrument [Line Items]
Carrying Value	266,255
Senior Financing	$ 1,962,750
Weighted Average Yield at End of Period	9.92%
Preferred Equity \| Total floating rate
Debt Instrument [Line Items]
Carrying Value	$ 0
Face Value	0
Preferred Equity \| Total fixed rate
Debt Instrument [Line Items]
Carrying Value	266,255
Face Value	$ 267,916
Minimum \| Senior Mortgage Debt \| Total fixed rate
Debt Instrument [Line Items]
Interest rate	3.50%
Minimum \| Mezzanine Debt \| Total fixed rate
Debt Instrument [Line Items]
Interest rate	2.90%
Minimum \| Preferred Equity \| Total fixed rate
Debt Instrument [Line Items]
Interest rate	6.50%
Maximum \| Mezzanine Debt \| Total fixed rate
Debt Instrument [Line Items]
Interest rate	14.30%
Maximum \| Preferred Equity \| Total fixed rate
Debt Instrument [Line Items]
Interest rate	11.00%
LIBOR \| Minimum \| Senior Mortgage Debt \| Total floating rate
Debt Instrument [Line Items]
Basis spread on variable rate	3.50%
LIBOR \| Minimum \| Junior Mortgage Debt \| Total floating rate
Debt Instrument [Line Items]
Basis spread on variable rate	7.25%
LIBOR \| Minimum \| Mezzanine Debt \| Total floating rate
Debt Instrument [Line Items]
Basis spread on variable rate	4.95%
LIBOR \| Maximum \| Mezzanine Debt \| Total floating rate
Debt Instrument [Line Items]
Basis spread on variable rate	13.50%