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Regulatory Matters - MISO Return on Equity Complaints (Details) - FERC [Member] | Sep. 30, 2016 | Sep. 28, 2016
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Return on Equity Complaint 1 [Member] |  |
Loss Contingencies [Line Items] |  |
Requested Return on Equity Filed with the FERC by Third Party |  | 9.15%
FERC Authorized Return on Common Equity | 10.32% |
Return on Equity Complaint 2 [Member] |  |
Loss Contingencies [Line Items] |  |
Requested Return on Equity Filed with the FERC by Third Party | 8.67% |
Proposed Return on Equity by Federal Administrative Law Judge | 9.70% |
Incentive Adder [Member] |  |
Loss Contingencies [Line Items] |  |
FERC Approved Incentive Adder for Participation in Regional Transmission Organization | 0.50 |

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- Definition FERC Authorized Return on Common Equity + References No definition available. + Details
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- Definition Incentive Adder for Participation in Regional Transmission Organization + References No definition available. + Details
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Namespace Prefix: | ale_
Data Type: | xbrli:pureItemType
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- Definition The proposed return on common equity by regulatory organization + References No definition available. + Details
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- Definition The requested return on common equity, which would be dedicated to the utilities within the regulatory organizations jurisdiction. + References No definition available. + Details
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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. + References No definition available. + Details
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- Details
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- Details
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- Details
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