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v3.19.2

Revenue from Contract with Customers - Additional Information (Details) $ in Billions | 6 Months Ended
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Jun. 30, 2019 USD ($)
Disaggregation of Revenue [Line Items] |
Revenue, remaining performance obligation | $ 3.2
ASUS | Contracted Services |
Disaggregation of Revenue [Line Items] |
Period of fixed price contracts to operate and maintain water systems at various military bases | 50 years
ASUS | Minimum |
Disaggregation of Revenue [Line Items] |
Revenue, remaining performance obligation, expected timing of satisfaction, explanation | P35Y
ASUS | Maximum |
Disaggregation of Revenue [Line Items] |
Revenue, remaining performance obligation, expected timing of satisfaction, explanation | P49Y
Sales | GOLDEN STATE WATER COMPANY | Water Service Utility Operations [Member] |
Disaggregation of Revenue [Line Items] |
Concentration Risk, Percentage | 90.00%
Sales | GOLDEN STATE WATER COMPANY | Electric Service Utility Operations |
Disaggregation of Revenue [Line Items] |
Concentration Risk, Percentage | 85.00%

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