Legal Proceedings	3 Months Ended
Mar. 31, 2019
Commitments and Contingencies Disclosure [Abstract]
LEGAL PROCEEDINGS	Legal Proceedings Class Action Suits Related to the Merger On June 14, 2018, certain shareholders of CTWS filed two nearly identical class-action complaints in Connecticut state court against the CTWS board of directors, SJW Group, Eric W. Thornburg, Chairman, President and Chief Executive Officer of SJW Group, and CTWS. The complaints, as amended on September 18, 2018 and September 20, 2018, allege that the CTWS board breached its fiduciary duties in connection with the Merger, that CTWS’s preliminary proxy statement, filed with the SEC on August 20, 2018, omits certain material information and that SJW Group and Mr. Thornburg aided and abetted the alleged breaches by the CTWS board of directors. Among other remedies, the actions seek to recover rescissory and other damages and attorney’s fees and costs. SJW Group believes the claims in these complaints are without merit and intends to vigorously defend this litigation. The parties to the lawsuits have agreed in principle to settle the lawsuits in exchange for the issuance of additional disclosures by CTWS. Pursuant to the agreements to settle the lawsuits, the plaintiffs have reserved the right to seek a mootness fee from CTWS. The parties moved to stay proceedings, other than fee-related proceedings, until such time as the transaction closes, and the court granted the parties’ motion to stay on November 14, 2018. On November 20, 2018, the plaintiffs filed an opening brief in support of their fee application. The stay of proceedings expired on February 28, 2019. On March 1, 2019, the court granted the parties’ motion to continue the stay and ordered that the stay is continued until May 29, 2019. Pursuant to the agreement in principle to settle the litigation, the complaints will be dismissed at such time as the transaction closes. SJW Group has determined that the likelihood of loss related to these class-action complaints is remote. Additional complaints have been filed in connection with the Merger but neither SJW Group nor any of its officers or directors are named as defendants therein. On October 5, 2018, certain shareholders of CTWS filed two complaints, one individually and the other as a putative class action, in the United States District Court for the District of Connecticut against CTWS and the CTWS board of directors. The complaints allege that the preliminary proxy statement issued in connection with the Merger omitted material information in violation of Section 14(a) and 20(a) of the Securities Exchange Act of 1934. Among other remedies, the actions seek an order (1) enjoining the defendants from consummating or closing on the Merger; (2) rescinding the Merger or awarding rescissory damages; (3) directing the defendants to disseminate a corrective proxy statement; (4) declaring that the defendants have violated Section 14(a) and/or 20(a) of the Securities Exchange Act of 1934, as well as Rule 14a-9 promulgated thereunder; and (5) awarding attorney’s fees and costs. SJW Group believes the claims in these complaints are without merit. CTWS has entered into an agreement in principle to settle and release all claims that were or could have been alleged by the plaintiffs. The settlements provide for the dismissal of the actions subject to, among other things, CTWS making certain additional disclosures, which CTWS included in the definitive proxy statement in connection with the Merger. Billing Practice OII with CPUC On September 14, 2018, the CPUC issued OII No. 18-09-003 to which San Jose Water Company was named as Respondent. The OII will determine whether the company unlawfully overcharged customers over a 30-year period by failing to pro-rate service charges when increases occurred during a billing period, and whether the company double-billed service charges during one billing period when allegedly switching from billing such charges in advance to billing in arrears. By a decision adopted November 29, 2018, in San Jose Water Company’s then-pending GRC, the CPUC approved a settlement to resolve the alleged overcharging issue for the period since June 2011 by requiring refunds to customers totaling $2,020. That amount was refunded to customers pursuant to San Jose Water Company’s Advice Letter No. 530, effective February 8, 2019. See discussion on the matter in Note 9, “Regulatory Rate Filings.” The CPUC investigation pursuant to OII No. 18-09-003 may result in liability for San Jose Water Company in addition to the $2,020 credited to customers pursuant to the CPUC’s November 29, 2018 decision. Such additional liability could result from a possible CPUC requirement that refunds or penalties be paid based on alleged over-billing prior to June 1, 2011. SJW Group is not able to make a reasonable estimate of the additional potential loss amount, if any, at this time. 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.

Legal Proceedings

Class Action Suits Related to the Merger

On June 14, 2018, certain shareholders of CTWS filed two nearly identical class-action complaints in Connecticut state court against the CTWS board of directors, SJW Group, Eric W. Thornburg, Chairman, President and Chief Executive Officer of SJW Group, and CTWS. The complaints, as amended on September 18, 2018 and September 20, 2018, allege that the CTWS board breached its fiduciary duties in connection with the Merger, that CTWS’s preliminary proxy statement, filed with the SEC on August 20, 2018, omits certain material information and that SJW Group and Mr. Thornburg aided and abetted the alleged breaches by the CTWS board of directors. Among other remedies, the actions seek to recover rescissory and other damages and attorney’s fees and costs. SJW Group believes the claims in these complaints are without merit and intends to vigorously defend this litigation. The parties to the lawsuits have agreed in principle to settle the lawsuits in exchange for the issuance of additional disclosures by CTWS. Pursuant to the agreements to settle the lawsuits, the plaintiffs have reserved the right to seek a mootness fee from CTWS. The parties moved to stay proceedings, other than fee-related proceedings, until such time as the transaction closes, and the court granted the parties’ motion to stay on November 14, 2018. On November 20, 2018, the plaintiffs filed an opening brief in support of their fee application. The stay of proceedings expired on February 28, 2019. On March 1, 2019, the court granted the parties’ motion to continue the stay and ordered that the stay is continued until May 29, 2019. Pursuant to the agreement in principle to settle the litigation, the complaints will be dismissed at such time as the transaction closes. SJW Group has determined that the likelihood of loss related to these class-action complaints is remote.

Additional complaints have been filed in connection with the Merger but neither SJW Group nor any of its officers or directors are named as defendants therein. On October 5, 2018, certain shareholders of CTWS filed two complaints, one individually and the other as a putative class action, in the United States District Court for the District of Connecticut against CTWS and the CTWS board of directors. The complaints allege that the preliminary proxy statement issued in connection with the Merger omitted material information in violation of Section 14(a) and 20(a) of the Securities Exchange Act of 1934. Among other remedies, the actions seek an order (1) enjoining the defendants from consummating or closing on the Merger; (2) rescinding the Merger or awarding rescissory damages; (3) directing the defendants to disseminate a corrective proxy statement; (4) declaring that the defendants have violated Section 14(a) and/or 20(a) of the Securities Exchange Act of 1934, as well as Rule 14a-9 promulgated thereunder; and (5) awarding attorney’s fees and costs. SJW Group believes the claims in these complaints are without merit. CTWS has entered into an agreement in principle to settle and release all claims that were or could have been alleged by the plaintiffs. The settlements provide for the dismissal of the actions subject to, among other things, CTWS making certain additional disclosures, which CTWS included in the definitive proxy statement in connection with the Merger.

Billing Practice OII with CPUC

On September 14, 2018, the CPUC issued OII No. 18-09-003 to which San Jose Water Company was named as Respondent. The OII will determine whether the company unlawfully overcharged customers over a 30-year period by failing to pro-rate service charges when increases occurred during a billing period, and whether the company double-billed service charges during one billing period when allegedly switching from billing such charges in advance to billing in arrears. By a decision adopted November 29, 2018, in San Jose Water Company’s then-pending GRC, the CPUC approved a settlement to resolve the alleged overcharging issue for the period since June 2011 by requiring refunds to customers totaling $2,020. That amount was refunded to customers pursuant to San Jose Water Company’s Advice Letter No. 530, effective February 8, 2019. See discussion on the matter in Note 9, “Regulatory Rate Filings.” The CPUC investigation pursuant to OII No. 18-09-003 may result in liability for San Jose Water Company in addition to the $2,020 credited to customers pursuant to the CPUC’s November 29, 2018 decision. Such additional liability could result from a possible CPUC requirement that refunds or penalties be paid based on alleged over-billing prior to June 1, 2011. SJW Group is not able to make a reasonable estimate of the additional potential loss amount, if any, at this time.

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.