REVENUE RECOGNITION AND RECEIVABLES - Contract Acquisition Costs (Details) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2020 USD ($)	Jun. 30, 2020 USD ($)
Contract Acquisition Costs
Amortization of contract acquisition cost	$ 0.5	$ 1.0
Prepayments and other current assets
Contract Acquisition Costs
Short-term contract acquisition costs	1.7	1.7
Other assets
Contract Acquisition Costs
Long-term contract acquisition costs	$ 1.1	$ 1.1

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- Definition

Amount of amortization expense for asset recognized from cost incurred to obtain or fulfill contract with customer.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 340
-SubTopic 40
-Section 50
-Paragraph 3
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=68051541&loc=SL49131252-203054

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- Definition

Amount, after accumulated amortization and accumulated impairment loss, of asset recognized from cost incurred to obtain or fulfill contract with customer; classified as current.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 340
-SubTopic 40
-Section 50
-Paragraph 3
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=68051541&loc=SL49131252-203054

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- Definition

Amount, after accumulated amortization and accumulated impairment loss, of asset recognized from cost incurred to obtain or fulfill contract with customer; classified as noncurrent.

+ References

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