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Revenue from Contract with Customers - Additional Information (Details) - Sales	3 Months Ended
	Mar. 31, 2021
GOLDEN STATE WATER COMPANY | Water Service Utility Operations [Member]
Disaggregation of Revenue [Line Items]
Concentration Risk, Percentage	90.00%
Golden State Water Company and Bear Valley Electric Service Inc. | Electric Service Utility Operations
Disaggregation of Revenue [Line Items]
Concentration Risk, Percentage	90.00%

X

- Definition

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.

+ References

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- Definition

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+ References

No definition available.

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