COMMITMENTS AND CONTINGENCIES (Narrative) (Details) - USD ($) $ in Millions |
Mar. 31, 2018 |
Jan. 01, 2018 |
Dec. 31, 2017 |
|---|---|---|---|
| Loss Contingencies [Line Items] | Ìý | Ìý | Ìý |
| Loss Contingency Accrual | $ 5.0 | Ìý | Ìý |
| Loans to and accounts receivable from the Canadian Entities | 50.4 | $ 51.6 | $ 51.6 |
| Contingent claims | 54.3 | $ 55.6 | $ 55.6 |
| Michigan Electricity Matters [Member] | Ìý | Ìý | Ìý |
| Loss Contingencies [Line Items] | Ìý | Ìý | Ìý |
| Loss Contingency Accrual | $ 13.0 | Ìý | Ìý |
| X | ||||||||||
- Definition Loans to and accounts receivables from the Canadian Entities No definition available.
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- Definition Reserve for unasserted claims in CCAA No definition available.
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| X | ||||||||||
- 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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| X | ||||||||||
- Definition Amount of loss contingency liability. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Details
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