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Fair Value - Schedule of Quantitative Information (Details) $ in Thousands | 6 Months Ended
--- | ---
Jun. 30, 2024 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 | $ 50,357
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 | $ (7,981)
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 | 1.86
Transaction/Delivery Volumes | MMBTU | 41,259
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 | 2.34
Transaction/Delivery Volumes | MMBTU | 100,000
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 | 2.05
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 | 2.46
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 | 9.48
Transaction/Delivery Volumes | MMBTU | 310,000
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 | 6.7
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 | $ 130,000
Equity investments, time to liquidity event | 1 year 9 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 | $ 388,600
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 | $ 246,000
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 | 2027
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 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 | 0.36
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 | 5.9
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 | 1.95
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 | $ 14,000
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 | $ 245,000
Investment, Type [Extensible Enumeration] | Equity Funds [Member]

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Name: | us-gaap_MeasurementInputTypeAxis=ava_MeasurementInputAnnualRevenuesMember
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Data Type: | na
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Period Type: |