Long-Term Debt to Affiliated Trusts - Schedule of Distribution Rates Paid (Details) - Trust Preferred Securities Subject to Mandatory Redemption [Member]	Jun. 30, 2025	Dec. 31, 2024
Debt Instrument [Line Items]
Interest rate	5.47%	5.64%
Minimum [Member]
Debt Instrument [Line Items]
Interest rate	5.46%	5.64%
Maximum [Member]
Debt Instrument [Line Items]
Interest rate	5.64%	6.51%

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.

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+ Details

AVISTA CORP 10-Q