SUPPLEMENTARY FINANCIAL STATEMENT INFORMATION - Deferred Revenue (Details) - USD ($) $ in Millions |
3 Months Ended | 6 Months Ended | ||
|---|---|---|---|---|
Jun. 30, 2020 |
Jun. 30, 2019 |
Jun. 30, 2020 |
Jun. 30, 2019 |
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| Revenue Recognition, Multiple-deliverable Arrangements [Line Items] | Ìý | Ìý | Ìý | Ìý |
| Realization of deferred revenue | $ 0.0 | $ 0.0 | $ 34.6 | $ 0.0 |
| Other Current Liabilities [Member] | Ìý | Ìý | Ìý | Ìý |
| Revenue Recognition, Multiple-deliverable Arrangements [Line Items] | Ìý | Ìý | Ìý | Ìý |
| Opening balance as of January 1 | Ìý | Ìý | 22.1 | 21.0 |
| Contract With Customer, Liability, Period Increase (Decrease) | Ìý | Ìý | (17.2) | (5.5) |
| Closing balance as of June 30 | 4.9 | 15.5 | 4.9 | 15.5 |
| Other Noncurrent Liabilities [Member] | Ìý | Ìý | Ìý | Ìý |
| Revenue Recognition, Multiple-deliverable Arrangements [Line Items] | Ìý | Ìý | Ìý | Ìý |
| Opening balance as of January 1 | Ìý | Ìý | 25.7 | 38.5 |
| Contract With Customer, Liability, Period Increase (Decrease) | Ìý | Ìý | (25.7) | (4.2) |
| Closing balance as of June 30 | $ 0.0 | $ 34.3 | $ 0.0 | $ 34.3 |
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- Definition Contract With Customer, Liability, Period Increase (Decrease) No definition available.
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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. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of revenue recognized that was previously reported as deferred or unearned revenue. No definition available.
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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. No definition available.
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