DERIVATIVE INSTRUMENTS - Notional Amount (Details) - Derivative instruments not designated as hedging instruments - Interest Rate Swap	9 Months Ended
Sep. 30, 2021 USD ($) investmentInstrument	Dec. 31, 2020 USD ($) investmentInstrument
Derivative [Line Items]
Number of Instruments \| investmentInstrument	8	8
Notional Amount \| $	$ 1,120,690,000	$ 1,121,590,000
Weighted-Average Fix Pay Rate	1.70%
Weighted-Average Remaining Term in Years	1 year 6 months
Minimum \| One-month LIBOR
Derivative [Line Items]
Reference Rate	0.70%
Maximum \| One-month LIBOR
Derivative [Line Items]
Reference Rate	2.11%

Derivative Instruments, Weighted-Average Fix Pay Rate

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- Definition

Derivative Instruments, Weighted-Average Remaining Term in Years

+ References

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- Definition

Fixed interest rate related to the interest rate derivative.

+ References

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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.

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- Definition

Nominal or face amount used to calculate payment on derivative.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1B
-URI http://asc.fasb.org/extlink&oid=125515794&loc=SL5580258-113959

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1A
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=125515794&loc=SL5579245-113959

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- Definition

The number of derivative instruments of a particular group held by the entity.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1A
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-URI http://asc.fasb.org/extlink&oid=125515794&loc=SL5579245-113959

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-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1B
-URI http://asc.fasb.org/extlink&oid=125515794&loc=SL5580258-113959

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