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Employee Benefit Plans 5 (Details) - Pension Benefits - USD ($) $ in Thousands | 12 Months Ended
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Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018
Employee benefit plans |  |  |
Regulatory adjustment | $ 483 | $ 593 | $ 0
GSWC |  |  |
Employee benefit plans |  |  |
Regulatory adjustment | 483 | (593) | 1,700
Bear Valley Electric Service, Inc. |  |  |
Employee benefit plans |  |  |
Regulatory adjustment | $ 200 | $ 205 | $ 271

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- Definition The increase (decrease) during the reporting period in the value of other assets that are created when regulatory agencies permits public utilities to defer costs to the balance sheet. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=121586364&loc=d3e3602-108585 + Details
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