EBP, employer contribution, participant compensation percentage.

No definition available.

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- Definition

Employee benefit plan, employer contribution, participant compensation matched, vesting percentage.

+ References

No definition available.

+ Details

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- Definition

Employee benefit plan, IBEW chapter.

+ References

No definition available.

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- Definition

Employee benefit plan, non-elective employer contribution, participant compensation matched, vesting percentage.

+ References

No definition available.

+ Details

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- Definition

Employee benefit plan notes receivable from participants general loan term.

+ References

No definition available.

+ Details

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- Definition

Employee benefit plan notes receivable from participants interest rate of prime rate plus percentage.

+ References

No definition available.

+ Details

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- Definition

Employee benefit plan notes receivable from participants primary residence loan term.

+ References

No definition available.

+ Details

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Data Type:	xbrli:durationItemType
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Period Type:	duration

- Definition

Employee benefit plan participant consent required for vested interest distribution.

+ References

No definition available.

+ Details

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

- Definition

Employee benefit plan participant contribution pretax minimum annual compensation to total compensation percentage.

+ References

No definition available.

+ Details

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Namespace Prefix:	ava_
Data Type:	dtr-types:percentItemType
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Period Type:	duration

- Definition

Employee benefit plan participant contribution vesting description.

+ References

No definition available.

+ Details

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Data Type:	xbrli:stringItemType
Balance Type:	na
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- Definition

Employee benefit plan participant loan maturity year.

+ References

No definition available.

+ Details

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Namespace Prefix:	ava_
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Balance Type:	na
Period Type:	duration

- Definition

Employee benefit plan percentage of increase in plan participants contribution per year.

+ References

No definition available.

+ Details

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Namespace Prefix:	ava_
Data Type:	dtr-types:percentItemType
Balance Type:	na
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- Definition

Employee benefit plan vested interest distribution lump-sum payment.

+ References

No definition available.

+ Details

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

- Definition

Employee benefit plan vested interest distribution monthly installments period.

+ References

No definition available.

+ Details

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Namespace Prefix:	ava_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Employee benefit plan vested interest distribution period.

+ References

No definition available.

+ Details

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Namespace Prefix:	ava_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Employee benefit plan vested percentage.

+ References

No definition available.

+ Details

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Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

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.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 962
-SubTopic 205
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478416/962-205-50-1

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- Definition

Percentage of employer matching contribution on eligible participant contribution to employee stock purchase, saving, or similar plan (employee benefit plan (EBP)).

+ References

+ Details

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Period Type:	duration

- Definition

Percentage of participant compensation eligible for employer matching contribution for participant in employee stock purchase, saving, or similar plan (employee benefit plan (EBP)).

+ References

+ Details

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Balance Type:	na
Period Type:	duration

- Definition

Amount of plan asset, in forfeited nonvested account, no longer allocated to participant in employee stock purchase, saving, or similar plan (employee benefit plan (EBP)).

+ References

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Amount of decrease in forfeited nonvested account of employee stock purchase, saving, or similar plan (employee benefit plan (EBP)) from employer contribution.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 962
-SubTopic 325
-Name Accounting Standards Codification
-Section 55
-Paragraph 17
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478873/962-325-55-17

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 962
-SubTopic 205
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (j)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478416/962-205-50-1

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 962
-SubTopic 205
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.6A-04(5)(c))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477804/962-205-S99-1

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Namespace Prefix:	us-gaap-ebp_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Amount of maximum account balance that participant in employee stock purchase, saving, or similar plan (employee benefit plan (EBP)) can borrow.

+ References

+ Details

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Namespace Prefix:	us-gaap-ebp_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Percentage of maximum account balance that participant in employee stock purchase, saving, or similar plan (employee benefit plan (EBP)) can borrow to total participant account balance.

+ References

+ Details

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- Definition

Amount of minimum account balance that participant in employee stock purchase, saving, or similar plan (employee benefit plan (EBP)) can borrow.

+ References

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Percentage of eligible compensation contributed for participant automatically enrolled in employee stock purchase, saving, or similar plan (employee benefit plan (EBP)).

+ References

+ Details

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Balance Type:	na
Period Type:	duration

- Definition

Amount of maximum pretax annual compensation that participant in employee stock purchase, saving, or similar plan (employee benefit plan (EBP)), is permitted to contribute.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 962
-SubTopic 205
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478416/962-205-50-1

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Data Type:	xbrli:monetaryItemType
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- Definition

Interest rate on participant loan in schedule of asset held for investment of employee stock purchase, saving, or similar plan (employee benefit plan (EBP)).

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name Employee Retirement Income Security Act of 1974
-Number 2520
-Section 103
-Subsection 10
-Paragraph b
-Subparagraph (1)(i)(D)
-Publisher DOL-EBSA

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 962
-SubTopic 205
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.6A-05(a)(Schedule I))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477804/962-205-S99-1

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Description of the Plan - Additional Information (Details) - EBP 003		12 Months Ended
	Dec. 16, 2024 Chapter	Dec. 31, 2025 USD ($) Chapter	Dec. 31, 2024 USD ($)
EBP, Description of Plan [Line Items]
Percentage of before-tax contributions of eligible compensation		1.00%
Employee's annual before-tax contribution limitation amount \| $		$ 23,500	$ 23,000
Employee benefit plan, IBEW chapter	77
Employer non-elective contribution of eligible compensation	5.00%
Vesting percentage		100.00%
Employee benefit plan, employer contribution, participant compensation matched, vesting percentage		100.00%
Employee benefit plan, non-elective employer contribution, participant compensation matched, vesting percentage		100.00%
Employee benefit plan notes receivable from participants interest rate of prime rate plus percentage		1.00%
Employee benefit plan contribution vesting description		Participant contributions are 100% vested at all times. Participants vest 100% in the Company matching contribution after one year of service or upon death, disability or reaching normal retirement age. Participants vest 100% in the non-elective employer contribution after three years of service or upon death, disability or reaching normal retirement age.
Employee benefit plan, notes receivable from participant, minimum loan, amount \| $		$ 1,000
Employee benefit plan, notes receivable from participant, account, maximum borrowing, amount \| $		$ 50,000
Employee benefit plan, note receivable from participant, account, maximum borrowing, to total account, percentage		50.00%
Employee benefit plan, notes receivable from participants general loan		5 years
Employee benefit plan, notes receivable from participants primary residence loan term		10 years
Employee benefit plan participant loan maturity year		2034
Employee benefit plan, unused forfeited balances \| $		$ 86,951	296,568
Employee benefit plan forfeited balance used to reduce Company contribution \| $		$ 165,027	$ 1,752
Plan Participants Hired Prior to April 1, 2022
EBP, Description of Plan [Line Items]
Percentage of participants contribution		3.00%
Plan Participants Hired on or After April 1, 2022
EBP, Description of Plan [Line Items]
Percentage of participants contribution		6.00%
75% Employee Contributions
EBP, Description of Plan [Line Items]
Matching contribution percentage		75.00%
Percentage on employee eligible compensation		6.00%
Employees Hired Prior to January 1, 2006
EBP, Description of Plan [Line Items]
Employee benefit plan, IBEW chapter		659
Employees Hired Prior to January 1, 2011
EBP, Description of Plan [Line Items]
Employee benefit plan, IBEW chapter		77
Employees Hired on or After January 1, 2006
EBP, Description of Plan [Line Items]
Employee benefit plan, IBEW chapter		659
Employees Hired on or After January 1, 2011
EBP, Description of Plan [Line Items]
Employee benefit plan, IBEW chapter		77
100% Employee Contributions
EBP, Description of Plan [Line Items]
Matching contribution percentage		100.00%
Percentage on employee eligible compensation		6.00%
Employees Hired on or After January 1, 2014
EBP, Description of Plan [Line Items]
Employee benefit plan, IBEW chapter		77
Employees Hired on or After April 1, 2014
EBP, Description of Plan [Line Items]
Employee benefit plan, IBEW chapter		659
Employees Hired on or after April 1, 2017
EBP, Description of Plan [Line Items]
Employee benefit plan, IBEW chapter		77
Members Hired on or After January 1, 2024
EBP, Description of Plan [Line Items]
Employee benefit plan, IBEW chapter		77
Employer non-elective contribution of eligible compensation		5.00%
Minimum
EBP, Description of Plan [Line Items]
Employee benefit plan, interest rate		4.25%
Employee benefit plan participant consent required for vested interest distribution \| $		$ 1,000
Minimum \| Plan Participants Hired Prior to April 1, 2022
EBP, Description of Plan [Line Items]
Percentage of increase in plan participants contribution per year		1.00%
Minimum \| Plan Participants Hired on or After April 1, 2022
EBP, Description of Plan [Line Items]
Percentage of increase in plan participants contribution per year		1.00%
Maximum
EBP, Description of Plan [Line Items]
Employee benefit plan, interest rate		9.50%
Employee benefit plan vested interest distribution period		3 years
Employee benefit plan vested interest distribution monthly installments period		15 years
Employee benefit plan vested interest distribution lump-sum payment \| $		$ 1,000
Maximum \| Plan Participants Hired Prior to April 1, 2022
EBP, Description of Plan [Line Items]
Percentage of increase in plan participants contribution per year		15.00%
Maximum \| Plan Participants Hired on or After April 1, 2022
EBP, Description of Plan [Line Items]
Percentage of increase in plan participants contribution per year		15.00%