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| | | <ParentRole> http://www.gswater.com/role/BankDebt </ParentRole> |
| | | <Position> 38 </Position> |
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| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R39.htm </HtmlFileName> |
| | | <LongName> 9954480 - Disclosure - Long-Term Debt (Tables) </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.gswater.com/role/LongTermDebtTables </Role> |
| | | <ShortName> Long-Term Debt (Tables) </ShortName> |
| | | <MenuCategory> Tables </MenuCategory> |
| | | <ParentRole> http://www.gswater.com/role/LongTermDebt </ParentRole> |
| | | <Position> 39 </Position> |
| | | </Report> |
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| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R40.htm </HtmlFileName> |
| | | <LongName> 9954481 - Disclosure - Taxes on Income (Tables) </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.gswater.com/role/TaxesonIncomeTables </Role> |
| | | <ShortName> Taxes on Income (Tables) </ShortName> |
| | | <MenuCategory> Tables </MenuCategory> |
| | | <ParentRole> http://www.gswater.com/role/TaxesonIncome </ParentRole> |
| | | <Position> 40 </Position> |
| | | </Report> |
| | <Report instance="awr-20231231.htm"> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R41.htm </HtmlFileName> |
| | | <LongName> 9954482 - Disclosure - Employee Benefit Plans (Tables) </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.gswater.com/role/EmployeeBenefitPlansTables </Role> |
| | | <ShortName> Employee Benefit Plans (Tables) </ShortName> |
| | | <MenuCategory> Tables </MenuCategory> |
| | | <ParentRole> http://www.gswater.com/role/EmployeeBenefitPlans </ParentRole> |
| | | <Position> 41 </Position> |
| | | </Report> |
| | <Report instance="awr-20231231.htm"> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R42.htm </HtmlFileName> |
| | | <LongName> 9954483 - Disclosure - Stock-Based Compensation Plans (Tables) </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.gswater.com/role/StockBasedCompensationPlansTables </Role> |
| | | <ShortName> Stock-Based Compensation Plans (Tables) </ShortName> |
| | | <MenuCategory> Tables </MenuCategory> |
| | | <ParentRole> http://www.gswater.com/role/StockBasedCompensationPlans </ParentRole> |
| | | <Position> 42 </Position> |
| | | </Report> |
| | <Report instance="awr-20231231.htm"> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R43.htm </HtmlFileName> |
| | | <LongName> 9954484 - Disclosure - Commitments (Tables) </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.gswater.com/role/CommitmentsTables </Role> |
| | | <ShortName> Commitments (Tables) </ShortName> |
| | | <MenuCategory> Tables </MenuCategory> |
| | | <ParentRole> http://www.gswater.com/role/Commitments </ParentRole> |
| | | <Position> 43 </Position> |
| | | </Report> |
| | <Report instance="awr-20231231.htm"> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R44.htm </HtmlFileName> |
| | | <LongName> 9954485 - Disclosure - Leases (Tables) </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.gswater.com/role/LeasesTables </Role> |
| | | <ShortName> Leases (Tables) </ShortName> |
| | | <MenuCategory> Tables </MenuCategory> |
| | | <ParentRole> http://www.gswater.com/role/LeasesLeases </ParentRole> |
| | | <Position> 44 </Position> |
| | | </Report> |
| | <Report instance="awr-20231231.htm"> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R45.htm </HtmlFileName> |
| | | <LongName> 9954486 - Disclosure - Business Segments (Tables) </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.gswater.com/role/BusinessSegmentsTables </Role> |
| | | <ShortName> Business Segments (Tables) </ShortName> |
| | | <MenuCategory> Tables </MenuCategory> |
| | | <ParentRole> http://www.gswater.com/role/BusinessSegments </ParentRole> |
| | | <Position> 45 </Position> |
| | | </Report> |
| | <Report instance="awr-20231231.htm"> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R46.htm </HtmlFileName> |
| | | <LongName> 9954487 - Disclosure - Allowance for Doubtful Accounts (Tables) </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.gswater.com/role/AllowanceforDoubtfulAccountsTables </Role> |
| | | <ShortName> Allowance for Doubtful Accounts (Tables) </ShortName> |
| | | <MenuCategory> Tables </MenuCategory> |
| | | <ParentRole> http://www.gswater.com/role/AllowanceforDoubtfulAccounts </ParentRole> |
| | | <Position> 46 </Position> |
| | | </Report> |
| | <Report instance="awr-20231231.htm"> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R47.htm </HtmlFileName> |
| | | <LongName> 9954488 - Disclosure - Statement of Cash Flows, Supplemental Disclosures (Tables) </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.gswater.com/role/StatementofCashFlowsSupplementalDisclosuresTables </Role> |
| | | <ShortName> Statement of Cash Flows, Supplemental Disclosures (Tables) </ShortName> |
| | | <MenuCategory> Tables </MenuCategory> |
| | | <ParentRole> http://www.gswater.com/role/StatementofCashFlowsSupplementalDisclosures </ParentRole> |
| | | <Position> 47 </Position> |
| | | </Report> |
| | <Report instance="awr-20231231.htm"> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R48.htm </HtmlFileName> |
| | | <LongName> 9954489 - Disclosure - SCHEDULE I - CONDENSED FINANCIAL INFORMATION OF PARENT (Tables) </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.gswater.com/role/SCHEDULEICONDENSEDFINANCIALINFORMATIONOFPARENTTables </Role> |
| | | <ShortName> SCHEDULE I - CONDENSED FINANCIAL INFORMATION OF PARENT (Tables) </ShortName> |
| | | <MenuCategory> Tables </MenuCategory> |
| | | <ParentRole> http://www.gswater.com/role/SCHEDULEICONDENSEDFINANCIALINFORMATIONOFPARENT </ParentRole> |
| | | <Position> 48 </Position> |
| | | </Report> |
| | <Report instance="awr-20231231.htm"> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R49.htm </HtmlFileName> |
| | | <LongName> 9954490 - Disclosure - Summary of Significant Accounting Policies (Details) </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.gswater.com/role/SummaryofSignificantAccountingPoliciesDetails </Role> |
| | | <ShortName> Summary of Significant Accounting Policies (Details) </ShortName> |
| | | <MenuCategory> Details </MenuCategory> |
| | | <ParentRole> http://www.gswater.com/role/SummaryofSignificantAccountingPoliciesSummaryofSignificantAccountingPoliciesTables </ParentRole> |
| | | <Position> 49 </Position> |
| | | </Report> |
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| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R50.htm </HtmlFileName> |
| | | <LongName> 9954491 - Disclosure - Revenues (Details) </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.gswater.com/role/RevenuesDetails </Role> |
| | | <ShortName> Revenues (Details) </ShortName> |
| | | <MenuCategory> Details </MenuCategory> |
| | | <ParentRole> http://www.gswater.com/role/RevenuesTables </ParentRole> |
| | | <Position> 50 </Position> |
| | | </Report> |
| | <Report instance="awr-20231231.htm"> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R51.htm </HtmlFileName> |
| | | <LongName> 9954492 - Disclosure - Revenues Disaggregation of Revenue (Details) </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.gswater.com/role/RevenuesDisaggregationofRevenueDetails </Role> |
| | | <ShortName> Revenues Disaggregation of Revenue (Details) </ShortName> |
| | | <MenuCategory> Details </MenuCategory> |
| | | <Position> 51 </Position> |
| | | </Report> |
| | <Report instance="awr-20231231.htm"> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R52.htm </HtmlFileName> |
| | | <LongName> 9954493 - Disclosure - Revenues Contract assets and Contract Liabilities (Details) </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.gswater.com/role/RevenuesContractassetsandContractLiabilitiesDetails </Role> |
| | | <ShortName> Revenues Contract assets and Contract Liabilities (Details) </ShortName> |
| | | <MenuCategory> Details </MenuCategory> |
| | | <Position> 52 </Position> |
| | | </Report> |
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| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R53.htm </HtmlFileName> |
| | | <LongName> 9954494 - Disclosure - Regulatory Matters - Narrative (Details) </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.gswater.com/role/RegulatoryMattersNarrativeDetails </Role> |
| | | <ShortName> Regulatory Matters - Narrative (Details) </ShortName> |
| | | <MenuCategory> Details </MenuCategory> |
| | | <Position> 53 </Position> |
| | | </Report> |
| | <Report instance="awr-20231231.htm"> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R54.htm </HtmlFileName> |
| | | <LongName> 9954495 - Disclosure - Regulatory Matters - Schedule of Regulatory Liabilities and Assets (Details) </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.gswater.com/role/RegulatoryMattersScheduleofRegulatoryLiabilitiesandAssetsDetails </Role> |
| | | <ShortName> Regulatory Matters - Schedule of Regulatory Liabilities and Assets (Details) </ShortName> |
| | | <MenuCategory> Details </MenuCategory> |
| | | <Position> 54 </Position> |
| | | </Report> |
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| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R55.htm </HtmlFileName> |
| | | <LongName> 9954496 - Disclosure - Utility Plant and Intangible Assets - By Major Asset Class (Details) </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.gswater.com/role/UtilityPlantandIntangibleAssetsByMajorAssetClassDetails </Role> |
| | | <ShortName> Utility Plant and Intangible Assets - By Major Asset Class (Details) </ShortName> |
| | | <MenuCategory> Details </MenuCategory> |
| | | <Position> 55 </Position> |
| | | </Report> |
| | <Report instance="awr-20231231.htm"> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R56.htm </HtmlFileName> |
| | | <LongName> 9954497 - Disclosure - Utility Plant and Intangible Assets - Schedule of Components (Details) </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.gswater.com/role/UtilityPlantandIntangibleAssetsScheduleofComponentsDetails </Role> |
| | | <ShortName> Utility Plant and Intangible Assets - Schedule of Components (Details) </ShortName> |
| | | <MenuCategory> Details </MenuCategory> |
| | | <Position> 56 </Position> |
| | | </Report> |
| | <Report instance="awr-20231231.htm"> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R57.htm </HtmlFileName> |
| | | <LongName> 9954498 - Disclosure - Utility Plant and Intangible Assets - Schedule of Maturity (Details) </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.gswater.com/role/UtilityPlantandIntangibleAssetsScheduleofMaturityDetails </Role> |
| | | <ShortName> Utility Plant and Intangible Assets - Schedule of Maturity (Details) </ShortName> |
| | | <MenuCategory> Details </MenuCategory> |
| | | <Position> 57 </Position> |
| | | </Report> |
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| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R58.htm </HtmlFileName> |
| | | <LongName> 9954499 - Disclosure - Utility Plant and Intangible Assets - Narrative (Details) </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.gswater.com/role/UtilityPlantandIntangibleAssetsNarrativeDetails </Role> |
| | | <ShortName> Utility Plant and Intangible Assets - Narrative (Details) </ShortName> |
| | | <MenuCategory> Details </MenuCategory> |
| | | <Position> 58 </Position> |
| | | </Report> |
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| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R59.htm </HtmlFileName> |
| | | <LongName> 9954500 - Disclosure - Utility Plant and Intangible Assets - ARO Rollforward (Details) </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.gswater.com/role/UtilityPlantandIntangibleAssetsARORollforwardDetails </Role> |
| | | <ShortName> Utility Plant and Intangible Assets - ARO Rollforward (Details) </ShortName> |
| | | <MenuCategory> Details </MenuCategory> |
| | | <Position> 59 </Position> |
| | | </Report> |
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| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R60.htm </HtmlFileName> |
| | | <LongName> 9954501 - Disclosure - Derivative Instruments (Details) </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.gswater.com/role/DerivativeInstrumentsDetails </Role> |
| | | <ShortName> Derivative Instruments (Details) </ShortName> |
| | | <MenuCategory> Details </MenuCategory> |
| | | <ParentRole> http://www.gswater.com/role/DerivativeInstrumentsTables </ParentRole> |
| | | <Position> 60 </Position> |
| | | </Report> |
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| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R61.htm </HtmlFileName> |
| | | <LongName> 9954502 - Disclosure - Military Privatization (Details) </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.gswater.com/role/MilitaryPrivatizationDetails </Role> |
| | | <ShortName> Military Privatization (Details) </ShortName> |
| | | <MenuCategory> Details </MenuCategory> |
| | | <ParentRole> http://www.gswater.com/role/MilitaryPrivatization </ParentRole> |
| | | <Position> 61 </Position> |
| | | </Report> |
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| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R62.htm </HtmlFileName> |
| | | <LongName> 9954503 - Disclosure - Earnings Per Share / Capital Stock -Schedule of EPS (Details) </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.gswater.com/role/EarningsPerShareCapitalStockScheduleofEPSDetails </Role> |
| | | <ShortName> Earnings Per Share / Capital Stock -Schedule of EPS (Details) </ShortName> |
| | | <MenuCategory> Details </MenuCategory> |
| | | <Position> 62 </Position> |
| | | </Report> |
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| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R63.htm </HtmlFileName> |
| | | <LongName> 9954504 - Disclosure - Earnings Per Share / Capital Stock- Narrative (Details) </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.gswater.com/role/EarningsPerShareCapitalStockNarrativeDetails </Role> |
| | | <ShortName> Earnings Per Share / Capital Stock- Narrative (Details) </ShortName> |
| | | <MenuCategory> Details </MenuCategory> |
| | | <Position> 63 </Position> |
| | | </Report> |
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| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R64.htm </HtmlFileName> |
| | | <LongName> 9954505 - Disclosure - Dividend Limitations (Details) </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.gswater.com/role/DividendLimitationsDetails </Role> |
| | | <ShortName> Dividend Limitations (Details) </ShortName> |
| | | <MenuCategory> Details </MenuCategory> |
| | | <ParentRole> http://www.gswater.com/role/DividendLimitations </ParentRole> |
| | | <Position> 64 </Position> |
| | | </Report> |
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| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R65.htm </HtmlFileName> |
| | | <LongName> 9954506 - Disclosure - Bank Debt (Details) </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.gswater.com/role/BankDebtDetails </Role> |
| | | <ShortName> Bank Debt (Details) </ShortName> |
| | | <MenuCategory> Details </MenuCategory> |
| | | <ParentRole> http://www.gswater.com/role/BankDebtTables </ParentRole> |
| | | <Position> 65 </Position> |
| | | </Report> |
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| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R66.htm </HtmlFileName> |
| | | <LongName> 9954507 - Disclosure - Long-Term Debt (Details) </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.gswater.com/role/LongTermDebtDetails </Role> |
| | | <ShortName> Long-Term Debt (Details) </ShortName> |
| | | <MenuCategory> Details </MenuCategory> |
| | | <ParentRole> http://www.gswater.com/role/LongTermDebtTables </ParentRole> |
| | | <Position> 66 </Position> |
| | | </Report> |
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| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R67.htm </HtmlFileName> |
| | | <LongName> 9954508 - Disclosure - Long-Term Debt 2 (Details) </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.gswater.com/role/LongTermDebt2Details </Role> |
| | | <ShortName> Long-Term Debt 2 (Details) </ShortName> |
| | | <MenuCategory> Details </MenuCategory> |
| | | <ParentRole> http://www.gswater.com/role/LongTermDebtTables </ParentRole> |
| | | <Position> 67 </Position> |
| | | </Report> |
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| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R68.htm </HtmlFileName> |
| | | <LongName> 9954510 - Disclosure - Taxes on Income (Details) </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.gswater.com/role/TaxesonIncomeDetails </Role> |
| | | <ShortName> Taxes on Income (Details) </ShortName> |
| | | <MenuCategory> Details </MenuCategory> |
| | | <ParentRole> http://www.gswater.com/role/TaxesonIncomeTables </ParentRole> |
| | | <Position> 68 </Position> |
| | | </Report> |
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| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R69.htm </HtmlFileName> |
| | | <LongName> 9954511 - Disclosure - Employee Benefit Plans - Narrative (Details) </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.gswater.com/role/EmployeeBenefitPlansNarrativeDetails </Role> |
| | | <ShortName> Employee Benefit Plans - Narrative (Details) </ShortName> |
| | | <MenuCategory> Details </MenuCategory> |
| | | <Position> 69 </Position> |
| | | </Report> |
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| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R70.htm </HtmlFileName> |
| | | <LongName> 9954512 - Disclosure - Employee Benefit Plans - Funded Status of Pension Plan and Post-Retirement Medical Plan (Details) </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.gswater.com/role/EmployeeBenefitPlansFundedStatusofPensionPlanandPostRetirementMedicalPlanDetails </Role> |
| | | <ShortName> Employee Benefit Plans - Funded Status of Pension Plan and Post-Retirement Medical Plan (Details) </ShortName> |
| | | <MenuCategory> Details </MenuCategory> |
| | | <Position> 70 </Position> |
| | | </Report> |
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| | | <IsDefault> false </IsDefault> |
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| | | <HtmlFileName> R71.htm </HtmlFileName> |
| | | <LongName> 9954513 - Disclosure - Employee Benefit Plans - Pension Benefits and Post-Retirement Medical Benefits Recognized on Balance Sheet (Details) </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.gswater.com/role/EmployeeBenefitPlansPensionBenefitsandPostRetirementMedicalBenefitsRecognizedonBalanceSheetDetails </Role> |
| | | <ShortName> Employee Benefit Plans - Pension Benefits and Post-Retirement Medical Benefits Recognized on Balance Sheet (Details) </ShortName> |
| | | <MenuCategory> Details </MenuCategory> |
| | | <Position> 71 </Position> |
| | | </Report> |
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| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R72.htm </HtmlFileName> |
| | | <LongName> 9954514 - Disclosure - Employee Benefit Plans - Components of Net Periodic Pension Costs (Details) </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.gswater.com/role/EmployeeBenefitPlansComponentsofNetPeriodicPensionCostsDetails </Role> |
| | | <ShortName> Employee Benefit Plans - Components of Net Periodic Pension Costs (Details) </ShortName> |
| | | <MenuCategory> Details </MenuCategory> |
| | | <Position> 72 </Position> |
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