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v3.10.0.1

Income Taxes: (Details) | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2018 | Jun. 30, 2017 | Jun. 30, 2018 | Jun. 30, 2017
GOLDEN STATE WATER COMPANY |  |  |  |
Effective income tax rate |  |  |  |
ETRs (as a percent) | 23.60% | 39.80% | 21.90% | 38.80%
Parent [Member] |  |  |  |
Effective income tax rate |  |  |  |
ETRs (as a percent) | 21.20% | 38.60% | 20.40% | 37.40%

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