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Pension Plans and Other Postretirement Benefit Plans - Components of Net Periodic Benefit Costs (Parenthetical) (Details) | 12 Months Ended |
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Dec. 31, 2024 | Dec. 31, 2022
Defined Benefit Plan Disclosure [Line Items] |  |
Percentage of service related net periodic benefit costs capitalized to utility property | 45.00% |
Percentage of service related net periodic benefit costs recorded to operating expenses | 55.00% |
Pension Plan and SERP [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Regulatory asset amortization period |  | 12 years

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- Definition Percentage of service related net periodic benefit costs capitalized to utility property. + References No definition available. + Details
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- Definition Percentage of service related net periodic benefit costs recorded to operating expenses. + References No definition available. + Details
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Namespace Prefix: | ava_
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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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- Definition Amortization period for the recovery of regulatory asset, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + References No definition available. + Details
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- Details
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Period Type: |