XML 33 R16.htm IDEA: XBRL DOCUMENT
v3.8.0.1

Contingencies | 12 Months Ended
--- | ---
Dec. 31, 2017
Legal Proceedings [Abstract] |
Contingencies | Contingencies SJW Group is subject to ordinary routine litigation incidental to its business. There are no pending legal proceedings to which SJW Group or any of its subsidiaries is a party, or to which any of its properties is the subject, that are expected to have a material effect on SJW Group’s business, financial position, results of operations or cash flows.

X
- Definition Legal Proceedings [Abstract] + References No definition available. + Details
Name: | sjw_LegalProceedingsAbstract
Namespace Prefix: | sjw_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition The entire disclosure for legal proceedings, legal contingencies, litigation, regulatory and environmental matters and other contingencies. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 450 -URI http://asc.fasb.org/topic&trid=2127136 + Details
Name: | us-gaap_LegalMattersAndContingenciesTextBlock
Namespace Prefix: | us-gaap_
Data Type: | nonnum:textBlockItemType
Balance Type: | na
Period Type: | duration