DERIVATIVE INSTRUMENTS - Schedule of Derivatives (Details) - Cash Flow Hedges - Designated as Hedging Instrument - USD ($)	Jun. 30, 2021	Dec. 31, 2020
Derivative [Line Items]
Estimated Fair Value, Asset (Liability)	$ (62,736,000)	$ (93,769,000)
1-Month USD LIBOR
Derivative [Line Items]
Notional amount	1,775,000,000	1,875,000,000
1-Month USD LIBOR \| Interest Rate Swap Designated March 27, 2017
Derivative [Line Items]
Notional amount	$ 0	100,000,000
Fixed Interest Rate	1.971%
Estimated Fair Value, Asset (Liability)	$ 0	(929,000)
1-Month USD LIBOR \| Interest Rate Swap Designated December 13, 2017 Tranche 1
Derivative [Line Items]
Notional amount	$ 300,000,000	300,000,000
Fixed Interest Rate	2.201%
Estimated Fair Value, Asset (Liability)	$ (9,122,000)	(12,557,000)
1-Month USD LIBOR \| Interest Rate Swap Designated December 13, 2017 Tranche 3
Derivative [Line Items]
Notional amount	$ 150,000,000	150,000,000
Fixed Interest Rate	2.423%
Estimated Fair Value, Asset (Liability)	$ (8,692,000)	(11,502,000)
1-Month USD LIBOR \| Interest Rate Swap Designated December 13, 2017 Tranche 5
Derivative [Line Items]
Notional amount	$ 200,000,000	200,000,000
Fixed Interest Rate	2.313%
Estimated Fair Value, Asset (Liability)	$ (11,856,000)	(16,243,000)
1-Month USD LIBOR \| Interest Rate Swap Designated October 10, 2018 Tranche 1
Derivative [Line Items]
Notional amount	$ 75,000,000	75,000,000
Fixed Interest Rate	3.22%
Estimated Fair Value, Asset (Liability)	$ (7,595,000)	(9,836,000)
1-Month USD LIBOR \| Interest Rate Swap Designated October 10, 2018 Tranche 2
Derivative [Line Items]
Notional amount	$ 75,000,000	75,000,000
Fixed Interest Rate	3.199%
Estimated Fair Value, Asset (Liability)	$ (7,553,000)	(9,826,000)
1-Month USD LIBOR \| Interest Rate Swap Designated October 10, 2018 Tranche 3
Derivative [Line Items]
Notional amount	$ 75,000,000	75,000,000
Fixed Interest Rate	3.209%
Estimated Fair Value, Asset (Liability)	$ (7,541,000)	(9,783,000)
1-Month USD LIBOR \| Interest Rate Swap Designated December 18, 2018 Tranche 1
Derivative [Line Items]
Notional amount	$ 100,000,000	100,000,000
Fixed Interest Rate	2.885%
Estimated Fair Value, Asset (Liability)	$ (7,703,000)	(10,407,000)
1-Month USD LIBOR \| Interest Rate Swap Designated December 18, 2018 Tranche 2
Derivative [Line Items]
Notional amount	$ 100,000,000	100,000,000
Fixed Interest Rate	2.867%
Estimated Fair Value, Asset (Liability)	$ (7,592,000)	(10,431,000)
1-Month USD LIBOR \| Interest Rate Swap Designated December 15, 2020 Tranche 1
Derivative [Line Items]
Notional amount	$ 575,000,000	575,000,000
Fixed Interest Rate	1.415%
Estimated Fair Value, Asset (Liability)	$ 3,931,000	(1,907,000)
1-Month USD LIBOR \| Interest Rate Swap Designated December 15, 2020 Tranche 2
Derivative [Line Items]
Notional amount	$ 125,000,000	125,000,000
Fixed Interest Rate	1.404%
Estimated Fair Value, Asset (Liability)	$ 987,000	$ (348,000)

Fair value of the assets less the liabilities of a derivative or group of derivatives.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 10
-URI http://asc.fasb.org/extlink&oid=123594938&loc=d3e13433-108611

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Fixed interest rate related to the interest rate derivative.

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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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