Regulatory Matters - Schedule of Decoupling and Earnings Sharing Mechanisms (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
WASHINGTON \| Decoupling Rebate [Member]
Schedule of Decoupling and Earnings Sharing [Line Items]
Regulatory Liabilities	$ (3,232)	$ (13,210)
IDAHO \| Decoupling Rebate [Member]
Schedule of Decoupling and Earnings Sharing [Line Items]
Regulatory Liabilities	(7,961)	(7,889)
IDAHO \| Revenue Subject to Refund [Member]
Schedule of Decoupling and Earnings Sharing [Line Items]
Regulatory Liabilities	(572)	(686)
OREGON \| Decoupling Surcharge [Member]
Schedule of Decoupling and Earnings Sharing [Line Items]
Regulatory assets		$ 2,853
OREGON \| Decoupling Rebate [Member]
Schedule of Decoupling and Earnings Sharing [Line Items]
Regulatory Liabilities	$ (3,724)

[Line Items] for Schedule of Decoupling and Earnings Sharing [Table]

No definition available.

Name:	ava_ScheduleofDecouplingandEarningsSharingLineItems
Namespace Prefix:	ava_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

The amount for the individual regulatory asset as itemized in a table of regulatory assets as of the end of the period.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 980
-SubTopic 340
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481878/980-340-50-1

+ Details

Name:	us-gaap_RegulatoryAssets
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

The amount for the individual regulatory liability as itemized in a table of regulatory liabilities as of the end of the period.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 980
-SubTopic 405
-Name Accounting Standards Codification
-Section 25
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481854/980-405-25-1

+ Details

Name:	us-gaap_RegulatoryLiabilities
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Details

Name:	us-gaap_StatutoryAccountingPracticesByJurisdictionAxis=stpr_WA
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_RegulatoryLiabilityAxis=ava_DecouplingRebateMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_StatutoryAccountingPracticesByJurisdictionAxis=stpr_ID
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_RegulatoryLiabilityAxis=us-gaap_RevenueSubjectToRefundMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_StatutoryAccountingPracticesByJurisdictionAxis=stpr_OR
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_RegulatoryAssetAxis=ava_DecouplingSurchargeMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: