XML 46 R34.htm IDEA: XBRL DOCUMENT
v3.25.1

Benefit Plans - Narrative (Details) $ in Thousands | 3 Months Ended
--- | ---
Mar. 31, 2025 USD ($)
Defined Benefit Plan Disclosure [Line Items] |
Expected required and discretionary employer cash contributions | $ 6,113
Employer plan contributions | $ 1,477
CTWS Employees |
Defined Benefit Plan Disclosure [Line Items] |
Rate of compensation increase | 1.50%

X
- Definition Defined Benefit Plan, Rate Of Compensation Increase + References No definition available. + Details
Name: | sjw_DefinedBenefitPlanRateOfCompensationIncrease
Namespace Prefix: | sjw_
Data Type: | dtr-types1:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
Name: | us-gaap_DefinedBenefitPlanDisclosureLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Amount of contributions received and expected to be received by defined benefit plan from employer in current fiscal year. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 55 -Paragraph 18 -Publisher FASB -URI https://asc.fasb.org/1943274/2147480482/715-20-55-18 Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 6 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480506/715-20-50-6 + Details
Name: | us-gaap_DefinedBenefitPlanExpectedFutureEmployerContributionsCurrentFiscalYear
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Amount of discretionary contributions made by an employer to a defined contribution plan. + References No definition available. + Details
Name: | us-gaap_DefinedContributionPlanEmployerDiscretionaryContributionAmount
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Details
Name: | srt_TitleOfIndividualAxis=sjw_CTWSEmployeesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |