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v3.25.1

Fair Value - Schedule of Quantitative Information (Details) $ in Millions | 3 Months Ended
--- | ---
Mar. 31, 2025 USD ($) MMBTU $ / MMBTU
Fair Value, Recurring [Member] | Level 3 [Member] |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items] |
Equity investments | $ 52
Investment, Type [Extensible Enumeration] | Equity Funds [Member]
Fair Value, Recurring [Member] | Natural Gas Exchange Agreements [Member] |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items] |
Derivative Liability | $ (13)
Internally Derived Weighted Average Cost Of Gas [Member] | Purchase [Member] | Minimum [Member] | Natural Gas Exchange Agreements [Member] |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items] |
Derivative, Forward Price | $ / MMBTU | 2.08
Transaction/Delivery Volumes | MMBTU | 255,000
Internally Derived Weighted Average Cost Of Gas [Member] | Purchase [Member] | Maximum [Member] | Natural Gas Exchange Agreements [Member] |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items] |
Derivative, Forward Price | $ / MMBTU | 3.3
Transaction/Delivery Volumes | MMBTU | 635,000
Internally Derived Weighted Average Cost Of Gas [Member] | Purchase [Member] | Weighted Average [Member] | Natural Gas Exchange Agreements [Member] |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items] |
Derivative, Forward Price | $ / MMBTU | 2.49
Internally Derived Weighted Average Cost Of Gas [Member] | Sales [Member] | Minimum [Member] | Natural Gas Exchange Agreements [Member] |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items] |
Derivative, Forward Price | $ / MMBTU | 1.27
Transaction/Delivery Volumes | MMBTU | 75,000
Internally Derived Weighted Average Cost Of Gas [Member] | Sales [Member] | Maximum [Member] | Natural Gas Exchange Agreements [Member] |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items] |
Derivative, Forward Price | $ / MMBTU | 7.2
Transaction/Delivery Volumes | MMBTU | 312,495
Internally Derived Weighted Average Cost Of Gas [Member] | Sales [Member] | Weighted Average [Member] | Natural Gas Exchange Agreements [Member] |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items] |
Derivative, Forward Price | $ / MMBTU | 4.8
Market Approach [Member] | Minimum [Member] | Fair Value, Recurring [Member] |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items] |
Equity investments, comparable enterprise values | $ 130
Equity investments, time to liquidity event | 1 year 3 months
Investment, Type [Extensible Enumeration] | Equity Funds [Member]
Market Approach [Member] | Maximum [Member] | Fair Value, Recurring [Member] |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items] |
Equity investments, comparable enterprise values | $ 389
Investment, Type [Extensible Enumeration] | Equity Funds [Member]
Market Approach [Member] | Weighted Average [Member] | Fair Value, Recurring [Member] |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items] |
Equity investments, comparable enterprise values | $ 246
Investment, Type [Extensible Enumeration] | Equity Funds [Member]
Discounted Cash Flows [Member] | Fair Value, Recurring [Member] |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items] |
Equity investments, terminal date | 2029
Investment, Type [Extensible Enumeration] | Equity Funds [Member]
Discounted Cash Flows [Member] | Discount Rate [Member] | Fair Value, Recurring [Member] |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items] |
Equity investments, measurement input | 25
Investment, Type [Extensible Enumeration] | Equity Funds [Member]
Discounted Cash Flows [Member] | Market Multiple Exit Reduction [Member] | Fair Value, Recurring [Member] |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items] |
Equity investments, measurement input | 50
Investment, Type [Extensible Enumeration] | Equity Funds [Member]
Discounted Cash Flows [Member] | Revenue Market Multiples [Member] | Minimum [Member] | Fair Value, Recurring [Member] |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items] |
Equity investments, measurement input | 0.33
Investment, Type [Extensible Enumeration] | Equity Funds [Member]
Discounted Cash Flows [Member] | Revenue Market Multiples [Member] | Maximum [Member] | Fair Value, Recurring [Member] |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items] |
Equity investments, measurement input | 3.25
Investment, Type [Extensible Enumeration] | Equity Funds [Member]
Discounted Cash Flows [Member] | Revenue Market Multiples [Member] | Weighted Average [Member] | Fair Value, Recurring [Member] |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items] |
Equity investments, measurement input | 1.62
Investment, Type [Extensible Enumeration] | Equity Funds [Member]
Discounted Cash Flows [Member] | Annual Revenues [Member] | Minimum [Member] | Fair Value, Recurring [Member] |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items] |
Equity investments, annual revenues | $ 20
Investment, Type [Extensible Enumeration] | Equity Funds [Member]
Discounted Cash Flows [Member] | Annual Revenues [Member] | Maximum [Member] | Fair Value, Recurring [Member] |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items] |
Equity investments, annual revenues | $ 207
Investment, Type [Extensible Enumeration] | Equity Funds [Member]

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- Definition Fair value, after the effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. 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Name: | us-gaap_MeasurementInputTypeAxis=ava_MeasurementInputAnnualRevenuesMember
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Data Type: | na
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Period Type: |