DERIVATIVE FINANCIAL INSTRUMENTS AND HEDGING - Schedule of derivative financial instruments (Details) - Interest rate swaps	Mar. 31, 2018 USD ($) Instrument	Dec. 31, 2017 USD ($) Instrument	Oct. 02, 2017 USD ($) Instrument
Number of Instruments
Total \| Instrument			2
Notional Amount
Total			$ 100,000,000.0
Designated as hedges
Number of Instruments
Interest rate swaps (asset) \| Instrument	2	2
Interest rate swaps (liability) \| Instrument	1	1
Total \| Instrument	3	3
Notional Amount
Interest rate swaps (asset)	$ 200,000,000	$ 200,000,000
Interest rate swaps (liability)	75,000,000	75,000,000
Total	275,000,000	275,000,000
Fair Value
Interest rate swaps (asset)	5,084,000	1,509,000
Interest rate swaps (liability)	(21,000)	(190,000)
Total	$ 5,063,000	$ 1,319,000

Aggregate notional amount specified by the derivative(s). Expressed as an absolute value.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Article 12
-Section 13
-Sentence Column B

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+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 50
-Paragraph 3
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=51824906&loc=SL20225862-175312

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Nominal or face amount used to calculate payments on the derivative asset.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1A
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=84234895&loc=SL5579245-113959

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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.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 45
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=6945355&loc=d3e41228-113958

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Nominal or face amount used to calculate payments on the derivative liability.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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