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Derivative Instruments (Tables) | 3 Months Ended
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Mar. 31, 2021
GOLDEN STATE WATER COMPANY |
Derivative Instruments, Gain (Loss) [Line Items] |
Derivative Instruments | The following table presents changes in the fair value of the Level 3 derivatives for the three months ended March 31, 2021 and 2020. The change in fair value was due to an increase in energy prices during the three months ended March 31, 2021.
|  | For The Three Months Ended March 31, |
(dollars in thousands) |  | 2021 |  | 2020 |
Fair value at beginning of the period |  | $ | (1,537) |  |  | $ | (3,171) |  |
Unrealized gains (losses) on purchased power contracts |  | 2,761 |  |  | (1,109) |  |
Fair value at end of the period |  | $ | 1,224 |  |  | $ | (4,280) |  |

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