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v3.19.1

Income Taxes: (Details) | 3 Months Ended
--- | ---
Mar. 31, 2019 | Mar. 31, 2018
GOLDEN STATE WATER COMPANY |  |
Effective income tax rate |  |
ETRs (as a percent) | 19.00% | 19.20%
Parent [Member] |  |
Effective income tax rate |  |
ETRs (as a percent) | 20.50% | 19.20%

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