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Regulatory Matters - Great Northern Transmission Line (Details) - Great Northern Transmission Line [Member] $ in Millions | Sep. 30, 2017 USD ($) kV Miles
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Regulatory Matters [Line Items] |
Transmission Line Length (Miles) | Miles | 220
Transmission Line Capacity (kV) | kV | 500
Total Project Costs Incurred to Date | $ 66.9
Minimum [Member] |
Regulatory Matters [Line Items] |
Total Project Cost in the U.S. | 560.0
Maximum [Member] |
Regulatory Matters [Line Items] |
Total Project Cost in the U.S. | 710.0
Minnesota Power [Member] | Minimum [Member] |
Regulatory Matters [Line Items] |
Total Project Cost in the U.S. | 300.0
Minnesota Power [Member] | Maximum [Member] |
Regulatory Matters [Line Items] |
Total Project Cost in the U.S. | 350.0
Manitoba Hydro [Member] |
Regulatory Matters [Line Items] |
Project Costs Recovered from Counterparty | $ 36.8
MPUC [Member] | Minnesota Power [Member] |
Regulatory Matters [Line Items] |
Transmission Line Length (Miles) | Miles | 220
Transmission Line Capacity (kV) | kV | 500

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- Definition The estimated amount of certain capital expenditures related to environmental compliance, regulatory matters, or other commitments and/or contingencies. This estimate includes expenditures expected in future periods and expenditures made through the end of the current period. + References No definition available. + Details
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- Details
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