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COMMITMENTS AND CONTINGENCIES Narrative (Details) - USD ($) $ in Millions | Mar. 31, 2017 | Dec. 31, 2016
--- | --- | ---
Loss Contingencies [Line Items] |  |
Loans to and accounts receivable from the Canadian Entities | $ 49.0 | $ 48.6
Contingent Liabilities recognized in Consolidated Financials | 37.5 | 37.2
Michigan Electricity Matters [Member] |  |
Loss Contingencies [Line Items] |  |
Loss Contingency Accrual | 13.6 |
Fair Value, Inputs, Level 3 [Member] |  |
Loss Contingencies [Line Items] |  |
Loans to and accounts receivable from the Canadian Entities | 49.0 | 48.6
Contingent Liabilities recognized in Consolidated Financials | $ 37.5 | $ 37.2

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