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Regulatory Matters 5 (Details) - USD ($) $ in Thousands | Dec. 31, 2020 | Dec. 31, 2019
--- | --- | ---
Regulatory matters: |  |
Total | $ 16,539 | $ (2,450)
GSWC |  |
Regulatory matters: |  |
Total | 12,373 | (2,450)
GSWC | Pension Costs and Other Postretirement Benefit Costs |  |
Regulatory matters: |  |
Regulatory Assets | 66,600 |
Total | $ 65,576 | $ 40,693

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- Definition -- None. No documentation exists for this element. -- + References No definition available. + Details
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Namespace Prefix: | awr_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

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- Definition The net amount of all regulatory assets less all regulatory liabilities as of the end of the period. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 980 -SubTopic 340 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6499975&loc=d3e44250-110382 + Details
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- Definition The amount for the individual regulatory asset as itemized in a table of regulatory assets as of the end of the period. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 980 -SubTopic 340 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6499975&loc=d3e44250-110382 + Details
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Namespace Prefix: |
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- Details
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