XML 59 R68.htm IDEA: XBRL DOCUMENT v2.4.1.9

Segment and Non-Tariffed Business Reporting (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended								12 Months Ended
	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2014 subsidiaries reportable_segment	Dec. 31, 2013	Dec. 31, 2012
Segment Reporting Information [Line Items]
Number of Subsidiaries									4sjw_NumberOfSubsidiaries
Number of Reportable Segments									2us-gaap_NumberOfReportableSegments
Operating revenue	$ 69,286us-gaap_RegulatedOperatingRevenue	$ 125,430us-gaap_RegulatedOperatingRevenue	$ 70,356us-gaap_RegulatedOperatingRevenue	$ 54,596us-gaap_RegulatedOperatingRevenue	$ 67,262us-gaap_RegulatedOperatingRevenue	$ 85,238us-gaap_RegulatedOperatingRevenue	$ 74,230us-gaap_RegulatedOperatingRevenue	$ 50,139us-gaap_RegulatedOperatingRevenue	$ 319,668us-gaap_RegulatedOperatingRevenue	$ 276,869us-gaap_RegulatedOperatingRevenue	$ 261,547us-gaap_RegulatedOperatingRevenue
Utilities Operating Expense									226,790us-gaap_UtilitiesOperatingExpense	223,462us-gaap_UtilitiesOperatingExpense	206,250us-gaap_UtilitiesOperatingExpense
Operating Income (Loss)	15,589us-gaap_OperatingIncomeLoss	59,114us-gaap_OperatingIncomeLoss	12,121us-gaap_OperatingIncomeLoss	6,054us-gaap_OperatingIncomeLoss	11,351us-gaap_OperatingIncomeLoss	19,346us-gaap_OperatingIncomeLoss	16,937us-gaap_OperatingIncomeLoss	5,773us-gaap_OperatingIncomeLoss	92,878us-gaap_OperatingIncomeLoss	53,407us-gaap_OperatingIncomeLoss	55,297us-gaap_OperatingIncomeLoss
Net income	5,688us-gaap_NetIncomeLoss	38,366us-gaap_NetIncomeLoss	6,846us-gaap_NetIncomeLoss	906us-gaap_NetIncomeLoss	4,677us-gaap_NetIncomeLoss	8,950us-gaap_NetIncomeLoss	7,440us-gaap_NetIncomeLoss	1,317us-gaap_NetIncomeLoss	51,806us-gaap_NetIncomeLoss	22,384us-gaap_NetIncomeLoss	22,318us-gaap_NetIncomeLoss
Depreciation and amortization									37,905us-gaap_UtilitiesOperatingExpenseDepreciationAndAmortization	35,039us-gaap_UtilitiesOperatingExpenseDepreciationAndAmortization	33,098us-gaap_UtilitiesOperatingExpenseDepreciationAndAmortization
Provision for income taxes									24,971us-gaap_IncomeTaxExpenseBenefit	14,135us-gaap_IncomeTaxExpenseBenefit	15,542us-gaap_IncomeTaxExpenseBenefit
Assets	1,269,304us-gaap_Assets				1,109,986us-gaap_Assets				1,269,304us-gaap_Assets	1,109,986us-gaap_Assets
SJW Corp. [Member]
Segment Reporting Information [Line Items]
Operating revenue									319,668us-gaap_RegulatedOperatingRevenue / us-gaap_StatementBusinessSegmentsAxis = us-gaap_CorporateMember	276,869us-gaap_RegulatedOperatingRevenue / us-gaap_StatementBusinessSegmentsAxis = us-gaap_CorporateMember	261,547us-gaap_RegulatedOperatingRevenue / us-gaap_StatementBusinessSegmentsAxis = us-gaap_CorporateMember
Utilities Operating Expense									226,790us-gaap_UtilitiesOperatingExpense / us-gaap_StatementBusinessSegmentsAxis = us-gaap_CorporateMember	223,462us-gaap_UtilitiesOperatingExpense / us-gaap_StatementBusinessSegmentsAxis = us-gaap_CorporateMember	206,250us-gaap_UtilitiesOperatingExpense / us-gaap_StatementBusinessSegmentsAxis = us-gaap_CorporateMember
Operating Income (Loss)									92,878us-gaap_OperatingIncomeLoss / us-gaap_StatementBusinessSegmentsAxis = us-gaap_CorporateMember	53,407us-gaap_OperatingIncomeLoss / us-gaap_StatementBusinessSegmentsAxis = us-gaap_CorporateMember	55,297us-gaap_OperatingIncomeLoss / us-gaap_StatementBusinessSegmentsAxis = us-gaap_CorporateMember
Net income									51,806us-gaap_NetIncomeLoss / us-gaap_StatementBusinessSegmentsAxis = us-gaap_CorporateMember	22,384us-gaap_NetIncomeLoss / us-gaap_StatementBusinessSegmentsAxis = us-gaap_CorporateMember	22,318us-gaap_NetIncomeLoss / us-gaap_StatementBusinessSegmentsAxis = us-gaap_CorporateMember
Depreciation and amortization									37,905us-gaap_UtilitiesOperatingExpenseDepreciationAndAmortization / us-gaap_StatementBusinessSegmentsAxis = us-gaap_CorporateMember	35,039us-gaap_UtilitiesOperatingExpenseDepreciationAndAmortization / us-gaap_StatementBusinessSegmentsAxis = us-gaap_CorporateMember	33,098us-gaap_UtilitiesOperatingExpenseDepreciationAndAmortization / us-gaap_StatementBusinessSegmentsAxis = us-gaap_CorporateMember
Interest Expense									20,788us-gaap_InterestExpense / us-gaap_StatementBusinessSegmentsAxis = us-gaap_CorporateMember	19,922us-gaap_InterestExpense / us-gaap_StatementBusinessSegmentsAxis = us-gaap_CorporateMember	20,185us-gaap_InterestExpense / us-gaap_StatementBusinessSegmentsAxis = us-gaap_CorporateMember
Provision for income taxes									24,971us-gaap_IncomeTaxExpenseBenefit / us-gaap_StatementBusinessSegmentsAxis = us-gaap_CorporateMember	14,135us-gaap_IncomeTaxExpenseBenefit / us-gaap_StatementBusinessSegmentsAxis = us-gaap_CorporateMember	15,542us-gaap_IncomeTaxExpenseBenefit / us-gaap_StatementBusinessSegmentsAxis = us-gaap_CorporateMember
Assets	1,269,304us-gaap_Assets / us-gaap_StatementBusinessSegmentsAxis = us-gaap_CorporateMember				1,109,986us-gaap_Assets / us-gaap_StatementBusinessSegmentsAxis = us-gaap_CorporateMember				1,269,304us-gaap_Assets / us-gaap_StatementBusinessSegmentsAxis = us-gaap_CorporateMember	1,109,986us-gaap_Assets / us-gaap_StatementBusinessSegmentsAxis = us-gaap_CorporateMember	1,087,499us-gaap_Assets / us-gaap_StatementBusinessSegmentsAxis = us-gaap_CorporateMember
Regulated [Member] | Water Utility Services [Member]
Segment Reporting Information [Line Items]
Operating revenue									306,474us-gaap_RegulatedOperatingRevenue / us-gaap_PublicUtilityRegulatedOrUnregulatedStatusAxis = us-gaap_RegulatedOperationMember / us-gaap_StatementBusinessSegmentsAxis = sjw_ReportableSegmentOneMember	264,782us-gaap_RegulatedOperatingRevenue / us-gaap_PublicUtilityRegulatedOrUnregulatedStatusAxis = us-gaap_RegulatedOperationMember / us-gaap_StatementBusinessSegmentsAxis = sjw_ReportableSegmentOneMember	251,032us-gaap_RegulatedOperatingRevenue / us-gaap_PublicUtilityRegulatedOrUnregulatedStatusAxis = us-gaap_RegulatedOperationMember / us-gaap_StatementBusinessSegmentsAxis = sjw_ReportableSegmentOneMember
Utilities Operating Expense									216,914us-gaap_UtilitiesOperatingExpense / us-gaap_PublicUtilityRegulatedOrUnregulatedStatusAxis = us-gaap_RegulatedOperationMember / us-gaap_StatementBusinessSegmentsAxis = sjw_ReportableSegmentOneMember	212,761us-gaap_UtilitiesOperatingExpense / us-gaap_PublicUtilityRegulatedOrUnregulatedStatusAxis = us-gaap_RegulatedOperationMember / us-gaap_StatementBusinessSegmentsAxis = sjw_ReportableSegmentOneMember	197,893us-gaap_UtilitiesOperatingExpense / us-gaap_PublicUtilityRegulatedOrUnregulatedStatusAxis = us-gaap_RegulatedOperationMember / us-gaap_StatementBusinessSegmentsAxis = sjw_ReportableSegmentOneMember
Operating Income (Loss)									89,560us-gaap_OperatingIncomeLoss / us-gaap_PublicUtilityRegulatedOrUnregulatedStatusAxis = us-gaap_RegulatedOperationMember / us-gaap_StatementBusinessSegmentsAxis = sjw_ReportableSegmentOneMember	52,021us-gaap_OperatingIncomeLoss / us-gaap_PublicUtilityRegulatedOrUnregulatedStatusAxis = us-gaap_RegulatedOperationMember / us-gaap_StatementBusinessSegmentsAxis = sjw_ReportableSegmentOneMember	53,139us-gaap_OperatingIncomeLoss / us-gaap_PublicUtilityRegulatedOrUnregulatedStatusAxis = us-gaap_RegulatedOperationMember / us-gaap_StatementBusinessSegmentsAxis = sjw_ReportableSegmentOneMember
Net income									50,612us-gaap_NetIncomeLoss / us-gaap_PublicUtilityRegulatedOrUnregulatedStatusAxis = us-gaap_RegulatedOperationMember / us-gaap_StatementBusinessSegmentsAxis = sjw_ReportableSegmentOneMember	23,273us-gaap_NetIncomeLoss / us-gaap_PublicUtilityRegulatedOrUnregulatedStatusAxis = us-gaap_RegulatedOperationMember / us-gaap_StatementBusinessSegmentsAxis = sjw_ReportableSegmentOneMember	22,811us-gaap_NetIncomeLoss / us-gaap_PublicUtilityRegulatedOrUnregulatedStatusAxis = us-gaap_RegulatedOperationMember / us-gaap_StatementBusinessSegmentsAxis = sjw_ReportableSegmentOneMember
Depreciation and amortization									35,926us-gaap_UtilitiesOperatingExpenseDepreciationAndAmortization / us-gaap_PublicUtilityRegulatedOrUnregulatedStatusAxis = us-gaap_RegulatedOperationMember / us-gaap_StatementBusinessSegmentsAxis = sjw_ReportableSegmentOneMember	33,067us-gaap_UtilitiesOperatingExpenseDepreciationAndAmortization / us-gaap_PublicUtilityRegulatedOrUnregulatedStatusAxis = us-gaap_RegulatedOperationMember / us-gaap_StatementBusinessSegmentsAxis = sjw_ReportableSegmentOneMember	31,085us-gaap_UtilitiesOperatingExpenseDepreciationAndAmortization / us-gaap_PublicUtilityRegulatedOrUnregulatedStatusAxis = us-gaap_RegulatedOperationMember / us-gaap_StatementBusinessSegmentsAxis = sjw_ReportableSegmentOneMember
Interest Expense									17,555us-gaap_InterestExpense / us-gaap_PublicUtilityRegulatedOrUnregulatedStatusAxis = us-gaap_RegulatedOperationMember / us-gaap_StatementBusinessSegmentsAxis = sjw_ReportableSegmentOneMember	16,616us-gaap_InterestExpense / us-gaap_PublicUtilityRegulatedOrUnregulatedStatusAxis = us-gaap_RegulatedOperationMember / us-gaap_StatementBusinessSegmentsAxis = sjw_ReportableSegmentOneMember	16,499us-gaap_InterestExpense / us-gaap_PublicUtilityRegulatedOrUnregulatedStatusAxis = us-gaap_RegulatedOperationMember / us-gaap_StatementBusinessSegmentsAxis = sjw_ReportableSegmentOneMember
Provision for income taxes									24,210us-gaap_IncomeTaxExpenseBenefit / us-gaap_PublicUtilityRegulatedOrUnregulatedStatusAxis = us-gaap_RegulatedOperationMember / us-gaap_StatementBusinessSegmentsAxis = sjw_ReportableSegmentOneMember	14,446us-gaap_IncomeTaxExpenseBenefit / us-gaap_PublicUtilityRegulatedOrUnregulatedStatusAxis = us-gaap_RegulatedOperationMember / us-gaap_StatementBusinessSegmentsAxis = sjw_ReportableSegmentOneMember	15,678us-gaap_IncomeTaxExpenseBenefit / us-gaap_PublicUtilityRegulatedOrUnregulatedStatusAxis = us-gaap_RegulatedOperationMember / us-gaap_StatementBusinessSegmentsAxis = sjw_ReportableSegmentOneMember
Assets	1,180,583us-gaap_Assets / us-gaap_PublicUtilityRegulatedOrUnregulatedStatusAxis = us-gaap_RegulatedOperationMember / us-gaap_StatementBusinessSegmentsAxis = sjw_ReportableSegmentOneMember				1,013,229us-gaap_Assets / us-gaap_PublicUtilityRegulatedOrUnregulatedStatusAxis = us-gaap_RegulatedOperationMember / us-gaap_StatementBusinessSegmentsAxis = sjw_ReportableSegmentOneMember				1,180,583us-gaap_Assets / us-gaap_PublicUtilityRegulatedOrUnregulatedStatusAxis = us-gaap_RegulatedOperationMember / us-gaap_StatementBusinessSegmentsAxis = sjw_ReportableSegmentOneMember	1,013,229us-gaap_Assets / us-gaap_PublicUtilityRegulatedOrUnregulatedStatusAxis = us-gaap_RegulatedOperationMember / us-gaap_StatementBusinessSegmentsAxis = sjw_ReportableSegmentOneMember	991,866us-gaap_Assets / us-gaap_PublicUtilityRegulatedOrUnregulatedStatusAxis = us-gaap_RegulatedOperationMember / us-gaap_StatementBusinessSegmentsAxis = sjw_ReportableSegmentOneMember
Regulated [Member] | SJW Corp. [Member]
Segment Reporting Information [Line Items]
Operating revenue									306,474us-gaap_RegulatedOperatingRevenue / us-gaap_PublicUtilityRegulatedOrUnregulatedStatusAxis = us-gaap_RegulatedOperationMember / us-gaap_StatementBusinessSegmentsAxis = us-gaap_CorporateMember	264,782us-gaap_RegulatedOperatingRevenue / us-gaap_PublicUtilityRegulatedOrUnregulatedStatusAxis = us-gaap_RegulatedOperationMember / us-gaap_StatementBusinessSegmentsAxis = us-gaap_CorporateMember	251,032us-gaap_RegulatedOperatingRevenue / us-gaap_PublicUtilityRegulatedOrUnregulatedStatusAxis = us-gaap_RegulatedOperationMember / us-gaap_StatementBusinessSegmentsAxis = us-gaap_CorporateMember
Utilities Operating Expense									216,914us-gaap_UtilitiesOperatingExpense / us-gaap_PublicUtilityRegulatedOrUnregulatedStatusAxis = us-gaap_RegulatedOperationMember / us-gaap_StatementBusinessSegmentsAxis = us-gaap_CorporateMember	212,761us-gaap_UtilitiesOperatingExpense / us-gaap_PublicUtilityRegulatedOrUnregulatedStatusAxis = us-gaap_RegulatedOperationMember / us-gaap_StatementBusinessSegmentsAxis = us-gaap_CorporateMember	197,893us-gaap_UtilitiesOperatingExpense / us-gaap_PublicUtilityRegulatedOrUnregulatedStatusAxis = us-gaap_RegulatedOperationMember / us-gaap_StatementBusinessSegmentsAxis = us-gaap_CorporateMember
Operating Income (Loss)									89,560us-gaap_OperatingIncomeLoss / us-gaap_PublicUtilityRegulatedOrUnregulatedStatusAxis = us-gaap_RegulatedOperationMember / us-gaap_StatementBusinessSegmentsAxis = us-gaap_CorporateMember	52,021us-gaap_OperatingIncomeLoss / us-gaap_PublicUtilityRegulatedOrUnregulatedStatusAxis = us-gaap_RegulatedOperationMember / us-gaap_StatementBusinessSegmentsAxis = us-gaap_CorporateMember	53,139us-gaap_OperatingIncomeLoss / us-gaap_PublicUtilityRegulatedOrUnregulatedStatusAxis = us-gaap_RegulatedOperationMember / us-gaap_StatementBusinessSegmentsAxis = us-gaap_CorporateMember
Net income									50,612us-gaap_NetIncomeLoss / us-gaap_PublicUtilityRegulatedOrUnregulatedStatusAxis = us-gaap_RegulatedOperationMember / us-gaap_StatementBusinessSegmentsAxis = us-gaap_CorporateMember	23,273us-gaap_NetIncomeLoss / us-gaap_PublicUtilityRegulatedOrUnregulatedStatusAxis = us-gaap_RegulatedOperationMember / us-gaap_StatementBusinessSegmentsAxis = us-gaap_CorporateMember	22,811us-gaap_NetIncomeLoss / us-gaap_PublicUtilityRegulatedOrUnregulatedStatusAxis = us-gaap_RegulatedOperationMember / us-gaap_StatementBusinessSegmentsAxis = us-gaap_CorporateMember
Depreciation and amortization									35,926us-gaap_UtilitiesOperatingExpenseDepreciationAndAmortization / us-gaap_PublicUtilityRegulatedOrUnregulatedStatusAxis = us-gaap_RegulatedOperationMember / us-gaap_StatementBusinessSegmentsAxis = us-gaap_CorporateMember	33,067us-gaap_UtilitiesOperatingExpenseDepreciationAndAmortization / us-gaap_PublicUtilityRegulatedOrUnregulatedStatusAxis = us-gaap_RegulatedOperationMember / us-gaap_StatementBusinessSegmentsAxis = us-gaap_CorporateMember	31,085us-gaap_UtilitiesOperatingExpenseDepreciationAndAmortization / us-gaap_PublicUtilityRegulatedOrUnregulatedStatusAxis = us-gaap_RegulatedOperationMember / us-gaap_StatementBusinessSegmentsAxis = us-gaap_CorporateMember
Interest Expense									17,555us-gaap_InterestExpense / us-gaap_PublicUtilityRegulatedOrUnregulatedStatusAxis = us-gaap_RegulatedOperationMember / us-gaap_StatementBusinessSegmentsAxis = us-gaap_CorporateMember	16,616us-gaap_InterestExpense / us-gaap_PublicUtilityRegulatedOrUnregulatedStatusAxis = us-gaap_RegulatedOperationMember / us-gaap_StatementBusinessSegmentsAxis = us-gaap_CorporateMember	16,499us-gaap_InterestExpense / us-gaap_PublicUtilityRegulatedOrUnregulatedStatusAxis = us-gaap_RegulatedOperationMember / us-gaap_StatementBusinessSegmentsAxis = us-gaap_CorporateMember
Provision for income taxes									24,210us-gaap_IncomeTaxExpenseBenefit / us-gaap_PublicUtilityRegulatedOrUnregulatedStatusAxis = us-gaap_RegulatedOperationMember / us-gaap_StatementBusinessSegmentsAxis = us-gaap_CorporateMember	14,446us-gaap_IncomeTaxExpenseBenefit / us-gaap_PublicUtilityRegulatedOrUnregulatedStatusAxis = us-gaap_RegulatedOperationMember / us-gaap_StatementBusinessSegmentsAxis = us-gaap_CorporateMember	15,678us-gaap_IncomeTaxExpenseBenefit / us-gaap_PublicUtilityRegulatedOrUnregulatedStatusAxis = us-gaap_RegulatedOperationMember / us-gaap_StatementBusinessSegmentsAxis = us-gaap_CorporateMember
Assets	1,180,583us-gaap_Assets / us-gaap_PublicUtilityRegulatedOrUnregulatedStatusAxis = us-gaap_RegulatedOperationMember / us-gaap_StatementBusinessSegmentsAxis = us-gaap_CorporateMember				1,013,229us-gaap_Assets / us-gaap_PublicUtilityRegulatedOrUnregulatedStatusAxis = us-gaap_RegulatedOperationMember / us-gaap_StatementBusinessSegmentsAxis = us-gaap_CorporateMember				1,180,583us-gaap_Assets / us-gaap_PublicUtilityRegulatedOrUnregulatedStatusAxis = us-gaap_RegulatedOperationMember / us-gaap_StatementBusinessSegmentsAxis = us-gaap_CorporateMember	1,013,229us-gaap_Assets / us-gaap_PublicUtilityRegulatedOrUnregulatedStatusAxis = us-gaap_RegulatedOperationMember / us-gaap_StatementBusinessSegmentsAxis = us-gaap_CorporateMember	991,866us-gaap_Assets / us-gaap_PublicUtilityRegulatedOrUnregulatedStatusAxis = us-gaap_RegulatedOperationMember / us-gaap_StatementBusinessSegmentsAxis = us-gaap_CorporateMember
Nonregulated [Member] | Water Utility Services [Member]
Segment Reporting Information [Line Items]
Operating revenue									6,175us-gaap_RegulatedOperatingRevenue / us-gaap_PublicUtilityRegulatedOrUnregulatedStatusAxis = us-gaap_UnregulatedOperationMember / us-gaap_StatementBusinessSegmentsAxis = sjw_ReportableSegmentOneMember	5,882us-gaap_RegulatedOperatingRevenue / us-gaap_PublicUtilityRegulatedOrUnregulatedStatusAxis = us-gaap_UnregulatedOperationMember / us-gaap_StatementBusinessSegmentsAxis = sjw_ReportableSegmentOneMember	5,523us-gaap_RegulatedOperatingRevenue / us-gaap_PublicUtilityRegulatedOrUnregulatedStatusAxis = us-gaap_UnregulatedOperationMember / us-gaap_StatementBusinessSegmentsAxis = sjw_ReportableSegmentOneMember
Utilities Operating Expense									4,686us-gaap_UtilitiesOperatingExpense / us-gaap_PublicUtilityRegulatedOrUnregulatedStatusAxis = us-gaap_UnregulatedOperationMember / us-gaap_StatementBusinessSegmentsAxis = sjw_ReportableSegmentOneMember	5,683us-gaap_UtilitiesOperatingExpense / us-gaap_PublicUtilityRegulatedOrUnregulatedStatusAxis = us-gaap_UnregulatedOperationMember / us-gaap_StatementBusinessSegmentsAxis = sjw_ReportableSegmentOneMember	4,043us-gaap_UtilitiesOperatingExpense / us-gaap_PublicUtilityRegulatedOrUnregulatedStatusAxis = us-gaap_UnregulatedOperationMember / us-gaap_StatementBusinessSegmentsAxis = sjw_ReportableSegmentOneMember
Operating Income (Loss)									1,489us-gaap_OperatingIncomeLoss / us-gaap_PublicUtilityRegulatedOrUnregulatedStatusAxis = us-gaap_UnregulatedOperationMember / us-gaap_StatementBusinessSegmentsAxis = sjw_ReportableSegmentOneMember	199us-gaap_OperatingIncomeLoss / us-gaap_PublicUtilityRegulatedOrUnregulatedStatusAxis = us-gaap_UnregulatedOperationMember / us-gaap_StatementBusinessSegmentsAxis = sjw_ReportableSegmentOneMember	1,480us-gaap_OperatingIncomeLoss / us-gaap_PublicUtilityRegulatedOrUnregulatedStatusAxis = us-gaap_UnregulatedOperationMember / us-gaap_StatementBusinessSegmentsAxis = sjw_ReportableSegmentOneMember
Net income									668us-gaap_NetIncomeLoss / us-gaap_PublicUtilityRegulatedOrUnregulatedStatusAxis = us-gaap_UnregulatedOperationMember / us-gaap_StatementBusinessSegmentsAxis = sjw_ReportableSegmentOneMember	(208)us-gaap_NetIncomeLoss / us-gaap_PublicUtilityRegulatedOrUnregulatedStatusAxis = us-gaap_UnregulatedOperationMember / us-gaap_StatementBusinessSegmentsAxis = sjw_ReportableSegmentOneMember	707us-gaap_NetIncomeLoss / us-gaap_PublicUtilityRegulatedOrUnregulatedStatusAxis = us-gaap_UnregulatedOperationMember / us-gaap_StatementBusinessSegmentsAxis = sjw_ReportableSegmentOneMember
Depreciation and amortization									359us-gaap_UtilitiesOperatingExpenseDepreciationAndAmortization / us-gaap_PublicUtilityRegulatedOrUnregulatedStatusAxis = us-gaap_UnregulatedOperationMember / us-gaap_StatementBusinessSegmentsAxis = sjw_ReportableSegmentOneMember	360us-gaap_UtilitiesOperatingExpenseDepreciationAndAmortization / us-gaap_PublicUtilityRegulatedOrUnregulatedStatusAxis = us-gaap_UnregulatedOperationMember / us-gaap_StatementBusinessSegmentsAxis = sjw_ReportableSegmentOneMember	360us-gaap_UtilitiesOperatingExpenseDepreciationAndAmortization / us-gaap_PublicUtilityRegulatedOrUnregulatedStatusAxis = us-gaap_UnregulatedOperationMember / us-gaap_StatementBusinessSegmentsAxis = sjw_ReportableSegmentOneMember
Interest Expense									0us-gaap_InterestExpense / us-gaap_PublicUtilityRegulatedOrUnregulatedStatusAxis = us-gaap_UnregulatedOperationMember / us-gaap_StatementBusinessSegmentsAxis = sjw_ReportableSegmentOneMember	0us-gaap_InterestExpense / us-gaap_PublicUtilityRegulatedOrUnregulatedStatusAxis = us-gaap_UnregulatedOperationMember / us-gaap_StatementBusinessSegmentsAxis = sjw_ReportableSegmentOneMember	0us-gaap_InterestExpense / us-gaap_PublicUtilityRegulatedOrUnregulatedStatusAxis = us-gaap_UnregulatedOperationMember / us-gaap_StatementBusinessSegmentsAxis = sjw_ReportableSegmentOneMember
Provision for income taxes									471us-gaap_IncomeTaxExpenseBenefit / us-gaap_PublicUtilityRegulatedOrUnregulatedStatusAxis = us-gaap_UnregulatedOperationMember / us-gaap_StatementBusinessSegmentsAxis = sjw_ReportableSegmentOneMember	124us-gaap_IncomeTaxExpenseBenefit / us-gaap_PublicUtilityRegulatedOrUnregulatedStatusAxis = us-gaap_UnregulatedOperationMember / us-gaap_StatementBusinessSegmentsAxis = sjw_ReportableSegmentOneMember	581us-gaap_IncomeTaxExpenseBenefit / us-gaap_PublicUtilityRegulatedOrUnregulatedStatusAxis = us-gaap_UnregulatedOperationMember / us-gaap_StatementBusinessSegmentsAxis = sjw_ReportableSegmentOneMember
Assets	18,071us-gaap_Assets / us-gaap_PublicUtilityRegulatedOrUnregulatedStatusAxis = us-gaap_UnregulatedOperationMember / us-gaap_StatementBusinessSegmentsAxis = sjw_ReportableSegmentOneMember				16,163us-gaap_Assets / us-gaap_PublicUtilityRegulatedOrUnregulatedStatusAxis = us-gaap_UnregulatedOperationMember / us-gaap_StatementBusinessSegmentsAxis = sjw_ReportableSegmentOneMember				18,071us-gaap_Assets / us-gaap_PublicUtilityRegulatedOrUnregulatedStatusAxis = us-gaap_UnregulatedOperationMember / us-gaap_StatementBusinessSegmentsAxis = sjw_ReportableSegmentOneMember	16,163us-gaap_Assets / us-gaap_PublicUtilityRegulatedOrUnregulatedStatusAxis = us-gaap_UnregulatedOperationMember / us-gaap_StatementBusinessSegmentsAxis = sjw_ReportableSegmentOneMember	13,245us-gaap_Assets / us-gaap_PublicUtilityRegulatedOrUnregulatedStatusAxis = us-gaap_UnregulatedOperationMember / us-gaap_StatementBusinessSegmentsAxis = sjw_ReportableSegmentOneMember
Nonregulated [Member] | Real Estate Services [Member]
Segment Reporting Information [Line Items]
Operating revenue									7,019us-gaap_RegulatedOperatingRevenue / us-gaap_PublicUtilityRegulatedOrUnregulatedStatusAxis = us-gaap_UnregulatedOperationMember / us-gaap_StatementBusinessSegmentsAxis = sjw_ReportableSegmentTwoMember	6,205us-gaap_RegulatedOperatingRevenue / us-gaap_PublicUtilityRegulatedOrUnregulatedStatusAxis = us-gaap_UnregulatedOperationMember / us-gaap_StatementBusinessSegmentsAxis = sjw_ReportableSegmentTwoMember	4,992us-gaap_RegulatedOperatingRevenue / us-gaap_PublicUtilityRegulatedOrUnregulatedStatusAxis = us-gaap_UnregulatedOperationMember / us-gaap_StatementBusinessSegmentsAxis = sjw_ReportableSegmentTwoMember
Utilities Operating Expense									4,193us-gaap_UtilitiesOperatingExpense / us-gaap_PublicUtilityRegulatedOrUnregulatedStatusAxis = us-gaap_UnregulatedOperationMember / us-gaap_StatementBusinessSegmentsAxis = sjw_ReportableSegmentTwoMember	4,000us-gaap_UtilitiesOperatingExpense / us-gaap_PublicUtilityRegulatedOrUnregulatedStatusAxis = us-gaap_UnregulatedOperationMember / us-gaap_StatementBusinessSegmentsAxis = sjw_ReportableSegmentTwoMember	3,379us-gaap_UtilitiesOperatingExpense / us-gaap_PublicUtilityRegulatedOrUnregulatedStatusAxis = us-gaap_UnregulatedOperationMember / us-gaap_StatementBusinessSegmentsAxis = sjw_ReportableSegmentTwoMember
Operating Income (Loss)									2,826us-gaap_OperatingIncomeLoss / us-gaap_PublicUtilityRegulatedOrUnregulatedStatusAxis = us-gaap_UnregulatedOperationMember / us-gaap_StatementBusinessSegmentsAxis = sjw_ReportableSegmentTwoMember	2,205us-gaap_OperatingIncomeLoss / us-gaap_PublicUtilityRegulatedOrUnregulatedStatusAxis = us-gaap_UnregulatedOperationMember / us-gaap_StatementBusinessSegmentsAxis = sjw_ReportableSegmentTwoMember	1,613us-gaap_OperatingIncomeLoss / us-gaap_PublicUtilityRegulatedOrUnregulatedStatusAxis = us-gaap_UnregulatedOperationMember / us-gaap_StatementBusinessSegmentsAxis = sjw_ReportableSegmentTwoMember
Net income									1,050us-gaap_NetIncomeLoss / us-gaap_PublicUtilityRegulatedOrUnregulatedStatusAxis = us-gaap_UnregulatedOperationMember / us-gaap_StatementBusinessSegmentsAxis = sjw_ReportableSegmentTwoMember	920us-gaap_NetIncomeLoss / us-gaap_PublicUtilityRegulatedOrUnregulatedStatusAxis = us-gaap_UnregulatedOperationMember / us-gaap_StatementBusinessSegmentsAxis = sjw_ReportableSegmentTwoMember	244us-gaap_NetIncomeLoss / us-gaap_PublicUtilityRegulatedOrUnregulatedStatusAxis = us-gaap_UnregulatedOperationMember / us-gaap_StatementBusinessSegmentsAxis = sjw_ReportableSegmentTwoMember
Depreciation and amortization									1,620us-gaap_UtilitiesOperatingExpenseDepreciationAndAmortization / us-gaap_PublicUtilityRegulatedOrUnregulatedStatusAxis = us-gaap_UnregulatedOperationMember / us-gaap_StatementBusinessSegmentsAxis = sjw_ReportableSegmentTwoMember	1,612us-gaap_UtilitiesOperatingExpenseDepreciationAndAmortization / us-gaap_PublicUtilityRegulatedOrUnregulatedStatusAxis = us-gaap_UnregulatedOperationMember / us-gaap_StatementBusinessSegmentsAxis = sjw_ReportableSegmentTwoMember	1,653us-gaap_UtilitiesOperatingExpenseDepreciationAndAmortization / us-gaap_PublicUtilityRegulatedOrUnregulatedStatusAxis = us-gaap_UnregulatedOperationMember / us-gaap_StatementBusinessSegmentsAxis = sjw_ReportableSegmentTwoMember
Interest Expense									1,022us-gaap_InterestExpense / us-gaap_PublicUtilityRegulatedOrUnregulatedStatusAxis = us-gaap_UnregulatedOperationMember / us-gaap_StatementBusinessSegmentsAxis = sjw_ReportableSegmentTwoMember	1,120us-gaap_InterestExpense / us-gaap_PublicUtilityRegulatedOrUnregulatedStatusAxis = us-gaap_UnregulatedOperationMember / us-gaap_StatementBusinessSegmentsAxis = sjw_ReportableSegmentTwoMember	1,511us-gaap_InterestExpense / us-gaap_PublicUtilityRegulatedOrUnregulatedStatusAxis = us-gaap_UnregulatedOperationMember / us-gaap_StatementBusinessSegmentsAxis = sjw_ReportableSegmentTwoMember
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