Number of the contracts with 15-year contracts with the U.S. government

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Number of construction performance obligation

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Represents the period of fixed price contracts to operate and maintain the water and/or wastewater systems at various military bases.

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Represents the number of months within which expected additional revenue collection is recorded when the difference between volumetric revenues as authorized by the CPUC for metered accounts (volumetric revenues) and the actual volumetric revenues recovered in customer rates results in an undercollection of revenues.

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- Definition

Retroactive water revenues impact as a result of a proposed decision for the full year of 2022

+ References

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For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

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The aggregate costs related to goods produced and sold and services rendered by an entity during the reporting period. This excludes costs incurred during the reporting period related to financial services rendered and other revenue generating activities.

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Revenues (Details) $ in Thousands	12 Months Ended
Revenues (Details) $ in Thousands	Dec. 31, 2024 USD ($) unit	Dec. 31, 2023 USD ($)	Dec. 31, 2022 USD ($)
Disaggregation of Revenue [Line Items]
Revenue, Performance Obligation, Payment Terms	20 days
Cost of services	$ 54,544	$ 57,912	$ 53,171
GSWC
Disaggregation of Revenue [Line Items]
Retroactive water revenues impact as a result of a proposed decision		32,000
Golden State Water Company and Bear Valley Electric Service, Inc.
Disaggregation of Revenue [Line Items]
Period within which Expected Additional Revenue Collection is Recorded Subject to Undercollection of Revenue	24 months
BVES
Disaggregation of Revenue [Line Items]
Retroactive water revenues impact as a result of a proposed decision	$ 3,700
Contracted services: \| American States Utility Services
Disaggregation of Revenue [Line Items]
Number of the contracts with 15-year contracts with the U.S. government \| unit	1
Number of construction performance obligation \| unit	1
Contracted services: \| American States Utility Services \| Maximum
Disaggregation of Revenue [Line Items]
Period of Fixed Price Contracts to Operate and Maintain Water Systems at Various Military Bases	50 years
Contracted services: \| American States Utility Services \| Minimum
Disaggregation of Revenue [Line Items]
Period of Fixed Price Contracts to Operate and Maintain Water Systems at Various Military Bases	15 years
Sales \| Water: \| GSWC \| Customer Concentration Risk
Disaggregation of Revenue [Line Items]
Percentage of total revenues	90.00%
Sales \| Electric: \| BVES \| Customer Concentration Risk
Disaggregation of Revenue [Line Items]
Percentage of total revenues	90.00%
Franchisor \| Golden State Water Company and Bear Valley Electric Service, Inc.
Disaggregation of Revenue [Line Items]
Cost of services	$ 4,600	$ 4,900	$ 4,000