Revenue - Schedule of Utilities Operating Revenue Expense Taxes (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
Revenue from Contract with Customer [Abstract]
Utility-related taxes	$ 17,086	$ 16,133	$ 43,667	$ 41,872

Public Utility Operating Expenses Excise Taxes Collected and Reported Gross in Revenues and Operating Expenses

No definition available.

Name:	ava_PublicUtilityOperatingExpensesExciseTaxesCollected
Namespace Prefix:	ava_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration