FAIR VALUE OF FINANCIAL INSTRUMENTS (Details) - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Cash and Cash Equivalents
Restricted Cash	$ 5.3	$ 7.2	$ 4.9
Carrying value
Cash and Cash Equivalents
Cash and cash equivalents	14.4	21.2
Restricted Cash	5.3	7.2
Variable rate debt	71.8	379.1
Fixed rate debt	688.3	579.3
Fair Value Measurement
Cash and Cash Equivalents
Cash and cash equivalents	14.4	21.2
Restricted Cash	5.3	7.2
Variable rate debt	71.8	379.1
Fixed rate debt	686.7	585.9
Quoted Prices in Active Markets (Level 1) \| Fair Value Measurement
Cash and Cash Equivalents
Cash and cash equivalents	14.4	21.2
Restricted Cash	5.3	7.2
Significant Observable Inputs (Level 2) \| Fair Value Measurement
Cash and Cash Equivalents
Variable rate debt	71.8	379.1
Fixed rate debt	$ 686.7	$ 585.9

Amount of cash and cash equivalents restricted as to withdrawal or usage. Cash includes, but is not limited to, currency on hand, demand deposits with banks or financial institutions, and other accounts with general characteristics of demand deposits. Cash equivalents include, but are not limited to, short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

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(a)(2))
-URI http://asc.fasb.org/extlink&oid=120400017&loc=d3e572229-122910

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(1))
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
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Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
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Reference 5: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant