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v3.21.1

Income Taxes: (Details) | 3 Months Ended
--- | ---
Mar. 31, 2021 | Mar. 31, 2020
Effective income tax rate |  |
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent | 21.00% |
Golden State Water Company |  |
Effective income tax rate |  |
ETRs ( as a percent) | 23.60% | 22.40%
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent | 21.00% |
Parent [Member] |  |
Effective income tax rate |  |
ETRs ( as a percent) | 23.50% | 21.70%

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