XML 18 R29.htm IDEA: XBRL DOCUMENT
v2.4.1.9

Defined Benfit Plan (Details) (USD $) In Thousands, unless otherwise specified | 3 Months Ended |
--- | --- | ---
Mar. 31, 2015 | Mar. 31, 2014 | Dec. 31, 2014
Components of Net Periodic Benefit Cost [Abstract] |  |  |  |  |
Service cost | $ 1,363 us-gaap_DefinedBenefitPlanServiceCost |  | $ 1,059 us-gaap_DefinedBenefitPlanServiceCost |  |
Interest cost | 1,711 us-gaap_DefinedBenefitPlanInterestCost |  | 1,651 us-gaap_DefinedBenefitPlanInterestCost |  |
Other cost | 1,192 us-gaap_DefinedBenefitPlanOtherCosts |  | 632 us-gaap_DefinedBenefitPlanOtherCosts |  |
Expected return on assets | (1,817)us-gaap_DefinedBenefitPlanExpectedReturnOnPlanAssets |  | (1,667)us-gaap_DefinedBenefitPlanExpectedReturnOnPlanAssets |  |
Net periodic benefit cost | 2,449 us-gaap_DefinedBenefitPlanNetPeriodicBenefitCost |  | 1,675 us-gaap_DefinedBenefitPlanNetPeriodicBenefitCost |  |
Plan Assets [Abstract] |  |  |  |  |
Fair value of plan assets | 105,325 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets |  |  | 103,879 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets |
Employer Contributions [Abstract] |  |  |  |  |
Estimated employer contributions for the current fiscal year | 8,077 sjw_DefinedBenefitPlanEstimatedTotalEmployerContributionsForCurrentFiscalYear |  |  |  |
Quoted Prices in Active Markets for Identical Assets |  |  |  |  |
Plan Assets [Abstract] |  |  |  |  |
Fair value of plan assets | 62,888 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member |  |  | 62,346 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member |
Significant Observable Inputs |  |  |  |  |
Plan Assets [Abstract] |  |  |  |  |
Fair value of plan assets | 42,437 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member |  |  | 41,533 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member |
Significant Unobservable Inputs |  |  |  |  |
Plan Assets [Abstract] |  |  |  |  |
Fair value of plan assets | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member |  |  | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member |
Equity Securities [Member] |  |  |  |  |
Plan Assets [Abstract] |  |  |  |  |
Target plan asset allocations | 55.00%us-gaap_DefinedBenefitPlanTargetPlanAssetAllocations / us-gaap_InvestmentTypeAxis = us-gaap_EquitySecuritiesMember |  | 55.00%us-gaap_DefinedBenefitPlanTargetPlanAssetAllocations / us-gaap_InvestmentTypeAxis = us-gaap_EquitySecuritiesMember |  |
Fixed Income Securities [Member] |  |  |  |  |
Plan Assets [Abstract] |  |  |  |  |
Target plan asset allocations | 45.00%us-gaap_DefinedBenefitPlanTargetPlanAssetAllocations / us-gaap_InvestmentTypeAxis = us-gaap_FixedIncomeSecuritiesMember |  | 45.00%us-gaap_DefinedBenefitPlanTargetPlanAssetAllocations / us-gaap_InvestmentTypeAxis = us-gaap_FixedIncomeSecuritiesMember |  |
Cash and cash equivalents |  |  |  |  |
Plan Assets [Abstract] |  |  |  |  |
Fair value of plan assets | 5,708 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_CashAndCashEquivalentsMember |  |  | 6,811 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_CashAndCashEquivalentsMember |
Cash and cash equivalents | Quoted Prices in Active Markets for Identical Assets |  |  |  |  |
Plan Assets [Abstract] |  |  |  |  |
Fair value of plan assets | 5,708 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_CashAndCashEquivalentsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member |  |  | 6,811 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_CashAndCashEquivalentsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member |
Cash and cash equivalents | Significant Observable Inputs |  |  |  |  |
Plan Assets [Abstract] |  |  |  |  |
Fair value of plan assets | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_CashAndCashEquivalentsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member |  |  | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_CashAndCashEquivalentsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member |
Cash and cash equivalents | Significant Unobservable Inputs |  |  |  |  |
Plan Assets [Abstract] |  |  |  |  |
Fair value of plan assets | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_CashAndCashEquivalentsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member |  |  | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_CashAndCashEquivalentsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member |
Actively Managed | All Cap Equity |  |  |  |  |
Plan Assets [Abstract] |  |  |  |  |
Fair value of plan assets | 4,232 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = sjw_ActivelyManagedInvestmentsMember / us-gaap_InvestmentTypeAxis = sjw_AllCapEquityFundMember | [1] |  | 4,266 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = sjw_ActivelyManagedInvestmentsMember / us-gaap_InvestmentTypeAxis = sjw_AllCapEquityFundMember | [1]
Actively Managed | All Cap Equity | Quoted Prices in Active Markets for Identical Assets |  |  |  |  |
Plan Assets [Abstract] |  |  |  |  |
Fair value of plan assets | 4,203 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = sjw_ActivelyManagedInvestmentsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_InvestmentTypeAxis = sjw_AllCapEquityFundMember | [1] |  | 4,237 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = sjw_ActivelyManagedInvestmentsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_InvestmentTypeAxis = sjw_AllCapEquityFundMember | [1]
Actively Managed | All Cap Equity | Significant Observable Inputs |  |  |  |  |
Plan Assets [Abstract] |  |  |  |  |
Fair value of plan assets | 29 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = sjw_ActivelyManagedInvestmentsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_InvestmentTypeAxis = sjw_AllCapEquityFundMember | [1] |  | 29 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = sjw_ActivelyManagedInvestmentsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_InvestmentTypeAxis = sjw_AllCapEquityFundMember | [1]
Actively Managed | All Cap Equity | Significant Unobservable Inputs |  |  |  |  |
Plan Assets [Abstract] |  |  |  |  |
Fair value of plan assets | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = sjw_ActivelyManagedInvestmentsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member / us-gaap_InvestmentTypeAxis = sjw_AllCapEquityFundMember | [1] |  | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = sjw_ActivelyManagedInvestmentsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member / us-gaap_InvestmentTypeAxis = sjw_AllCapEquityFundMember | [1]
Actively Managed | U.S. Large Cap Equity |  |  |  |  |
Plan Assets [Abstract] |  |  |  |  |
Fair value of plan assets | 36,233 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = sjw_ActivelyManagedInvestmentsMember / us-gaap_InvestmentTypeAxis = sjw_USLargeCapEquityMember | [1] |  | 35,489 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = sjw_ActivelyManagedInvestmentsMember / us-gaap_InvestmentTypeAxis = sjw_USLargeCapEquityMember | [1]
Actively Managed | U.S. Large Cap Equity | Quoted Prices in Active Markets for Identical Assets |  |  |  |  |
Plan Assets [Abstract] |  |  |  |  |
Fair value of plan assets | 36,233 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = sjw_ActivelyManagedInvestmentsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_InvestmentTypeAxis = sjw_USLargeCapEquityMember | [1] |  | 35,489 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = sjw_ActivelyManagedInvestmentsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_InvestmentTypeAxis = sjw_USLargeCapEquityMember | [1]
Actively Managed | U.S. Large Cap Equity | Significant Observable Inputs |  |  |  |  |
Plan Assets [Abstract] |  |  |  |  |
Fair value of plan assets | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = sjw_ActivelyManagedInvestmentsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_InvestmentTypeAxis = sjw_USLargeCapEquityMember | [1] |  | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = sjw_ActivelyManagedInvestmentsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_InvestmentTypeAxis = sjw_USLargeCapEquityMember | [1]
Actively Managed | U.S. Large Cap Equity | Significant Unobservable Inputs |  |  |  |  |
Plan Assets [Abstract] |  |  |  |  |
Fair value of plan assets | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = sjw_ActivelyManagedInvestmentsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member / us-gaap_InvestmentTypeAxis = sjw_USLargeCapEquityMember | [1] |  | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = sjw_ActivelyManagedInvestmentsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member / us-gaap_InvestmentTypeAxis = sjw_USLargeCapEquityMember | [1]
Actively Managed | U.S. Mid Cap Equity |  |  |  |  |
Plan Assets [Abstract] |  |  |  |  |
Fair value of plan assets | 6,330 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = sjw_ActivelyManagedInvestmentsMember / us-gaap_InvestmentTypeAxis = sjw_USMidCapEquityMember | [1] |  | 6,069 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = sjw_ActivelyManagedInvestmentsMember / us-gaap_InvestmentTypeAxis = sjw_USMidCapEquityMember | [1]
Actively Managed | U.S. Mid Cap Equity | Quoted Prices in Active Markets for Identical Assets |  |  |  |  |
Plan Assets [Abstract] |  |  |  |  |
Fair value of plan assets | 6,330 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = sjw_ActivelyManagedInvestmentsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_InvestmentTypeAxis = sjw_USMidCapEquityMember | [1] |  | 6,069 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = sjw_ActivelyManagedInvestmentsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_InvestmentTypeAxis = sjw_USMidCapEquityMember | [1]
Actively Managed | U.S. Mid Cap Equity | Significant Observable Inputs |  |  |  |  |
Plan Assets [Abstract] |  |  |  |  |
Fair value of plan assets | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = sjw_ActivelyManagedInvestmentsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_InvestmentTypeAxis = sjw_USMidCapEquityMember | [1] |  | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = sjw_ActivelyManagedInvestmentsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_InvestmentTypeAxis = sjw_USMidCapEquityMember | [1]
Actively Managed | U.S. Mid Cap Equity | Significant Unobservable Inputs |  |  |  |  |
Plan Assets [Abstract] |  |  |  |  |
Fair value of plan assets | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = sjw_ActivelyManagedInvestmentsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member / us-gaap_InvestmentTypeAxis = sjw_USMidCapEquityMember | [1] |  | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = sjw_ActivelyManagedInvestmentsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member / us-gaap_InvestmentTypeAxis = sjw_USMidCapEquityMember | [1]
Actively Managed | U.S. Small Cap Equity |  |  |  |  |
Plan Assets [Abstract] |  |  |  |  |
Fair value of plan assets | 5,444 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = sjw_ActivelyManagedInvestmentsMember / us-gaap_InvestmentTypeAxis = sjw_USSmallCapEquityMember | [1] |  | 4,982 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = sjw_ActivelyManagedInvestmentsMember / us-gaap_InvestmentTypeAxis = sjw_USSmallCapEquityMember | [1]
Actively Managed | U.S. Small Cap Equity | Quoted Prices in Active Markets for Identical Assets |  |  |  |  |
Plan Assets [Abstract] |  |  |  |  |
Fair value of plan assets | 5,444 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = sjw_ActivelyManagedInvestmentsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_InvestmentTypeAxis = sjw_USSmallCapEquityMember | [1] |  | 4,982 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = sjw_ActivelyManagedInvestmentsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_InvestmentTypeAxis = sjw_USSmallCapEquityMember | [1]
Actively Managed | U.S. Small Cap Equity | Significant Observable Inputs |  |  |  |  |
Plan Assets [Abstract] |  |  |  |  |
Fair value of plan assets | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = sjw_ActivelyManagedInvestmentsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_InvestmentTypeAxis = sjw_USSmallCapEquityMember | [1] |  | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = sjw_ActivelyManagedInvestmentsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_InvestmentTypeAxis = sjw_USSmallCapEquityMember | [1]
Actively Managed | U.S. Small Cap Equity | Significant Unobservable Inputs |  |  |  |  |
Plan Assets [Abstract] |  |  |  |  |
Fair value of plan assets | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = sjw_ActivelyManagedInvestmentsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member / us-gaap_InvestmentTypeAxis = sjw_USSmallCapEquityMember | [1] |  | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = sjw_ActivelyManagedInvestmentsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member / us-gaap_InvestmentTypeAxis = sjw_USSmallCapEquityMember | [1]
Actively Managed | Non-U.S. Large Cap Equity |  |  |  |  |
Plan Assets [Abstract] |  |  |  |  |
Fair value of plan assets | 4,970 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = sjw_ActivelyManagedInvestmentsMember / us-gaap_InvestmentTypeAxis = sjw_NonUSLargeCapEquityMember | [1] |  | 4,758 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = sjw_ActivelyManagedInvestmentsMember / us-gaap_InvestmentTypeAxis = sjw_NonUSLargeCapEquityMember | [1]
Actively Managed | Non-U.S. Large Cap Equity | Quoted Prices in Active Markets for Identical Assets |  |  |  |  |
Plan Assets [Abstract] |  |  |  |  |
Fair value of plan assets | 4,970 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = sjw_ActivelyManagedInvestmentsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_InvestmentTypeAxis = sjw_NonUSLargeCapEquityMember | [1] |  | 4,758 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = sjw_ActivelyManagedInvestmentsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_InvestmentTypeAxis = sjw_NonUSLargeCapEquityMember | [1]
Actively Managed | Non-U.S. Large Cap Equity | Significant Observable Inputs |  |  |  |  |
Plan Assets [Abstract] |  |  |  |  |
Fair value of plan assets | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = sjw_ActivelyManagedInvestmentsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_InvestmentTypeAxis = sjw_NonUSLargeCapEquityMember | [1] |  | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = sjw_ActivelyManagedInvestmentsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_InvestmentTypeAxis = sjw_NonUSLargeCapEquityMember | [1]
Actively Managed | Non-U.S. Large Cap Equity | Significant Unobservable Inputs |  |  |  |  |
Plan Assets [Abstract] |  |  |  |  |
Fair value of plan assets | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = sjw_ActivelyManagedInvestmentsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member / us-gaap_InvestmentTypeAxis = sjw_NonUSLargeCapEquityMember | [1] |  | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = sjw_ActivelyManagedInvestmentsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member / us-gaap_InvestmentTypeAxis = sjw_NonUSLargeCapEquityMember | [1]
Actively Managed | REIT |  |  |  |  |
Plan Assets [Abstract] |  |  |  |  |
Fair value of plan assets | 5,369 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = sjw_ActivelyManagedInvestmentsMember / us-gaap_InvestmentTypeAxis = sic_Z6798 | [1] |  | 5,069 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = sjw_ActivelyManagedInvestmentsMember / us-gaap_InvestmentTypeAxis = sic_Z6798 | [1]
Actively Managed | REIT | Quoted Prices in Active Markets for Identical Assets |  |  |  |  |
Plan Assets [Abstract] |  |  |  |  |
Fair value of plan assets | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = sjw_ActivelyManagedInvestmentsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_InvestmentTypeAxis = sic_Z6798 | [1] |  | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = sjw_ActivelyManagedInvestmentsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_InvestmentTypeAxis = sic_Z6798 | [1]
Actively Managed | REIT | Significant Observable Inputs |  |  |  |  |
Plan Assets [Abstract] |  |  |  |  |
Fair value of plan assets | 5,369 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = sjw_ActivelyManagedInvestmentsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_InvestmentTypeAxis = sic_Z6798 | [1] |  | 5,069 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = sjw_ActivelyManagedInvestmentsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_InvestmentTypeAxis = sic_Z6798 | [1]
Actively Managed | REIT | Significant Unobservable Inputs |  |  |  |  |
Plan Assets [Abstract] |  |  |  |  |
Fair value of plan assets | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = sjw_ActivelyManagedInvestmentsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member / us-gaap_InvestmentTypeAxis = sic_Z6798 | [1] |  | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = sjw_ActivelyManagedInvestmentsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member / us-gaap_InvestmentTypeAxis = sic_Z6798 | [1]
Fixed Income |  |  |  |  |
Plan Assets [Abstract] |  |  |  |  |
Fair value of plan assets | 37,039 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_FixedIncomeFundsMember | [2] |  | 36,435 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_FixedIncomeFundsMember | [2]
Fixed Income | Quoted Prices in Active Markets for Identical Assets |  |  |  |  |
Plan Assets [Abstract] |  |  |  |  |
Fair value of plan assets | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_FixedIncomeFundsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member | [2] |  | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_FixedIncomeFundsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member | [2]
Fixed Income | Significant Observable Inputs |  |  |  |  |
Plan Assets [Abstract] |  |  |  |  |
Fair value of plan assets | 37,039 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_FixedIncomeFundsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member | [2] |  | 36,435 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_FixedIncomeFundsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member | [2]
Fixed Income | Significant Unobservable Inputs |  |  |  |  |
Plan Assets [Abstract] |  |  |  |  |
Fair value of plan assets | $ 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_FixedIncomeFundsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member | [2] |  | $ 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_FixedIncomeFundsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member | [2]
[1] | Actively managed portfolio of securities with the goal to exceed the stated benchmark performance.
[2] | Actively managed portfolio of fixed income securities with the goal to exceed the Barclays 1-5 Year Government/Credit, Barclays Intermediate Government/Credit, and Merrill Lynch Preferred Stock Fixed Rate.

X
- Definition The employer's best estimate of total contributions expected to be paid to the plan for the current fiscal period. Estimated contributions may be presented in the aggregate combining (1) contributions required by funding regulations or laws, (2) discretionary contributions, and (3) noncash contributions. + References No definition available. + Details
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- Definition An amount calculated as a basis for determining the extent of delayed recognition of the effects of changes in the fair value of assets. The expected return on plan assets is determined based on the expected long-term rate of return on plan assets and the market-related value of plan assets. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 30 -Glossary Expected Return on Plan Assets -URI http://asc.fasb.org/extlink&oid=6512136 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 60 -Glossary Expected Return on Plan Assets -URI http://asc.fasb.org/extlink&oid=6512171 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (h)(3) -URI http://asc.fasb.org/extlink&oid=35743120&loc=d3e1928-114920 + Details
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- Definition Assets, usually stocks, bonds, and other investments, that have been segregated and restricted (usually in a trust) to provide benefits, at their fair value as of the measurement date. Plan assets include amounts contributed by the employer (and by employees for a contributory plan) and amounts earned from investing the contributions, less benefits paid. If a plan has liabilities other than for benefits, those non-benefit obligations may be considered as reductions of plan assets. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=35743120&loc=d3e1928-114920 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 30 -Section 35 -Paragraph 50 -URI http://asc.fasb.org/extlink&oid=29635418&loc=d3e12355-114930 + Details
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- Definition The increase in a defined benefit pension plan's projected benefit obligation or a defined benefit postretirement plan's accumulated postretirement benefit obligation due to the passage of time. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (h)(2) -URI http://asc.fasb.org/extlink&oid=35743120&loc=d3e1928-114920 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (a)(2) -URI http://asc.fasb.org/extlink&oid=35743120&loc=d3e1928-114920 + Details
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- Definition The total amount of net periodic benefit cost for defined benefit plans for the period. Periodic benefit costs include the following components: service cost, interest cost, expected return on plan assets, gain (loss), prior service cost or credit, transition asset or obligation, and gain (loss) due to settlements or curtailments. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (j) -URI http://asc.fasb.org/extlink&oid=35743120&loc=d3e1928-114920 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (h) -URI http://asc.fasb.org/extlink&oid=35743120&loc=d3e1928-114920 + Details
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- Definition Amount of other defined benefit plan costs. + References No definition available. + Details
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- Definition The actuarial present value of benefits attributed by the pension benefit formula to services rendered by employees during the period. The portion of the expected postretirement benefit obligation attributed to employee service during the period. The service cost component is a portion of the benefit obligation and is unaffected by the funded status of the plan. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (h)(1) -URI http://asc.fasb.org/extlink&oid=35743120&loc=d3e1928-114920 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Service Cost (Component of Net Periodic Pension Cost) -URI http://asc.fasb.org/extlink&oid=6525008 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=35743120&loc=d3e1928-114920 + Details
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