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Regulatory Matters - MISO Return on Equity Complaints (Details) - FERC [Member] | Dec. 31, 2022
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Loss Contingencies [Line Items] |
FERC Authorized Return on Common Equity | 10.02%
FERC Authorized Return on Equity Including Incentive Adder | 10.52%

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- Definition FERC Authorized Return on Common Equity + References No definition available. + Details
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- Definition FERC Authorized Return on Equity, Including Incentive Adder + References No definition available. + Details
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Namespace Prefix: | ale_
Data Type: | dtr-types:percentItemType
Balance Type: | na
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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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Balance Type: | na
Period Type: | duration

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- Details
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Period Type: |