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REVENUE (Deferred Revenue) (Details) - USD ($) $ in Millions | 9 Months Ended |  |
--- | --- | --- | ---
Sep. 30, 2019 | Sep. 30, 2018 | Dec. 31, 2018 | Dec. 31, 2017
Other Current Liabilities [Member] |  |  |  |
Deferred Revenue Arrangement [Line Items] |  |  |  |
Contract with Customer, Liability, Current | $ 18.3 | $ 16.1 | $ 21.0 | $ 23.8
Contract With Customer, Liability, Period Increase (Decrease) | (2.7) | (7.7) |  |
Other Noncurrent Liabilities [Member] |  |  |  |
Deferred Revenue Arrangement [Line Items] |  |  |  |
Contract with Customer, Liability, Noncurrent | 30.0 | 42.8 | $ 38.5 | $ 51.4
Contract With Customer, Liability, Period Increase (Decrease) | $ (8.5) | $ (8.6) |  |

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- Definition Amount of obligation to transfer good or service to customer for which consideration has been received or is receivable, classified as current. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 606 -SubTopic 10 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=118944033&loc=SL49130531-203044 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 606 -SubTopic 10 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=118944033&loc=SL49130532-203044 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 606 -SubTopic 10 -Section 50 -Paragraph 8 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=118956577&loc=SL49130549-203045 + Details
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