Bundled Purchased Renewable Energy Credits Number

No definition available.

Name:	awr_BundledPurchasedRenewableEnergyCreditsNumber
Namespace Prefix:	awr_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

Represents the period of agreement with a third party to purchase renewable energy credits.

+ References

No definition available.

+ Details

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

- Definition

Represents the number of renewable energy credits that would be purchased over a contractual period of time.

+ References

No definition available.

+ Details

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Namespace Prefix:	awr_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

Purchased Renewable Energy Credits Number Delivered in 2023

+ References

No definition available.

+ Details

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Namespace Prefix:	awr_
Data Type:	xbrli:integerItemType
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Period Type:	duration

- Definition

Purchased Renewable Energy Credits Number Delivered in 2024

+ References

No definition available.

+ Details

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Namespace Prefix:	awr_
Data Type:	xbrli:integerItemType
Balance Type:	na
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- 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

No definition available.

+ Details

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- Definition

Minimum amount to be expended to satisfy the terms of arrangements in which the entity has agreed to expend funds to procure goods or services, excluding long-term purchase commitments or unconditional purchase obligations.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 942
-SubTopic 210
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(17))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478546/942-210-S99-1

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 210
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(25))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1

+ Details

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Balance Type:	credit
Period Type:	instant

- Definition

Minimum amount of purchase arrangement in which the entity has agreed to expend funds to procure goods or services from a supplier.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
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Balance Type:	credit
Period Type:	instant

- Details

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- Details

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- Details

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- Details

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- Details

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- Details

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- Details

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- Details

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- Details

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Commitments - Narrative (Details) $ in Thousands	12 Months Ended
Commitments - Narrative (Details) $ in Thousands	Dec. 31, 2025 USD ($) unit	Dec. 31, 2024 unit	Dec. 31, 2023 unit
BVES
Purchase Commitment, Excluding Long-term Commitment [Line Items]
Number of renewable energy credits that would be purchased \| unit	578,000
Bundled Purchased Renewable Energy Credits Number \| unit	587,000
Purchased Renewable Energy Credits Number Delivered in 2023 \| unit			60,000
Purchased Renewable Energy Credits Number Delivered in 2024 \| unit	45,000	15,000
BVES \| Renewables Portfolio Standard
Purchase Commitment, Excluding Long-term Commitment [Line Items]
Derivative, term of contract	10 years
BVES \| Renewables Portfolio Standard (Bundled Product)
Purchase Commitment, Excluding Long-term Commitment [Line Items]
Derivative, term of contract	11 years
Water Supply \| GSWC
Purchase Commitment, Excluding Long-term Commitment [Line Items]
Purchase Obligation	$ 1,984
Water Supply \| GSWC \| Various third parties
Purchase Commitment, Excluding Long-term Commitment [Line Items]
Remaining amount of commitment	900
Water Supply \| GSWC \| Other various third parties
Purchase Commitment, Excluding Long-term Commitment [Line Items]
Purchase Obligation	1,100
Electric Power Purchase Commitments \| BVES
Purchase Commitment, Excluding Long-term Commitment [Line Items]
Purchase Obligation	53,300
Electric Renewable Energy Credit Purchase Commitments \| BVES
Purchase Commitment, Excluding Long-term Commitment [Line Items]
Purchase Obligation	$ 8,800