DERIVATIVE FINANCIAL INSTRUMENTS AND HEDGING - Schedule of derivative financial instruments (Details) - Designated as hedges - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Interest rate swaps
Derivative financial instruments and hedging
Notional Amount	$ 400,000	$ 400,000
Fair Value	$ (24,647)	(30,850)
Interest Rate Swap Expiring January 31, 2023 One
Derivative financial instruments and hedging
Average Annual Effective Fixed Rate	1.98%
Notional Amount	$ 100,000	100,000
Fair Value	$ (3,287)	(3,831)
Interest Rate Swap Expiring January 31, 2023 Two
Derivative financial instruments and hedging
Average Annual Effective Fixed Rate	1.98%
Notional Amount	$ 100,000	100,000
Fair Value	$ (3,305)	(3,853)
Interest Rate Swap Expiring September 30, 2024
Derivative financial instruments and hedging
Average Annual Effective Fixed Rate	2.87%
Notional Amount	$ 75,000	75,000
Fair Value	$ (6,066)	(7,371)
Interest Rate Swap Expiring December 31, 2025
Derivative financial instruments and hedging
Average Annual Effective Fixed Rate	2.93%
Notional Amount	$ 125,000	125,000
Fair Value	$ (11,989)	$ (15,795)

Fair values as of the balance sheet date of the net amount of all assets and liabilities resulting from contracts that meet the criteria of being accounted for as derivative instruments.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 45
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=117331979&loc=d3e41228-113958

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- Definition

Average fixed interest rate related to the group of interest rate derivatives.

+ 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.

+ References

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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=121590274&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=121590274&loc=SL5579245-113959

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