Regulatory Rate Filings	6 Months Ended
Jun. 30, 2018
Regulated Operations [Abstract]
Regulatory Rate Filings	Regulatory Rate Filings On January 4, 2018, San Jose Water Company filed General Rate Case Application No. 18-01-004 with the CPUC requesting authority for an increase of revenue of $34,288, or 9.76%, in 2019, $14,232, or 3.70%, in 2020 and $20,582, or 5.17%, in 2021. Among other things, the application also includes requests to recover $20,725 from balancing and memorandum accounts, the establishment of a Water Revenue Adjustment Mechanism and Sales Reconciliation Mechanism, and a shift to greater revenue collection in the service charge. On June 28, 2018, the CPUC issued an order in the case identifying the issues to be considered, including whether the proposed merger between SJW Group and Connecticut Water Service, Inc. will have any ratemaking impact on the customers of San Jose Water Company (see discussion on the proposed merger at Note 12). The application is in a year-long review process and new rates, if approved, are expected to become effective January 1, 2019. On March 14, 2018, San Jose Water Company filed Advice Letter No. 517 to update its Cost of Capital Memorandum Account, which tracks the difference between current water rates and those adopted in Decision 18-03-035. This was approved on April 4, 2018. The CPUC directed its Class A water utilities, including San Jose Water Company, to reflect the changes to the Internal Revenue Code resulting from the passage of the Tax Act in customer rates. On May 8, 2018, the CPUC directed San Jose Water Company to file an advice letter to implement a change in water rates to reflect the lower income tax rate provided by the Tax Act, effective July 1, 2018. On May 23, 2018, San Jose Water Company filed Advice Letter No. 522 in compliance with the CPUC’s directive. On June 7, 2018, San Jose Water Company filed Advice Letter No. 522A amending the rate change to reflect a reduction in revenue requirement for 2018 of $14,801 or 3.89%, with no impact on after tax income. This request became effective July 1, 2018. On June 13, 2018, San Jose Water Company filed Advice Letter No. 523 with the CPUC requesting authorization to implement surcharges to offset the increases to purchased potable water charges, the ground water extraction fee, and purchased recycled water charges implemented by the Santa Clara Valley Water District and South Bay Water Recycling effective July 1, 2018. The increases amount to a revenue increase of $13,732 or 3.75%. This request became effective July 1, 2018. San Jose Water Company filed Advice Letter No. 524 with the CPUC on July 26, 2018, requesting authorization to recover the 2017 capital additions related to the Montevina Water Treatment Plant Upgrade Project. The filing requests a revenue increase of $3,155 or 0.83% and is anticipated to become effective on or about August 25, 2018, pending the CPUC’s approval. The Public Utilities Commission of Texas (“PUCT”) directed CLWSC (as well as other Class A water utilities in Texas) to quantify all of the impacts of the passage of the Tax Act and make rate adjustments reflecting such impacts on a prospective basis. PUCT Order 47945-36 as amended by 47945-41 orders the water utilities to record a regulatory liability that reflects (1) the difference between the revenues collected under existing rates and the revenues that would have been collected had the existing rates been set using the recently approved federal income tax rates; and (2) the balance of excess accumulated deferred federal income taxes that now exists because of the decrease in the federal income tax rate from 35% to 21%. A rate proposal reflecting these tax changes was submitted for PUCT’s review on April 19, 2018. CLWSC subsequently amended their filing on April 30, 2018 to update the customer notice, and to replace estimates for April with recorded April 2018 information. This filing will return to the ratepayers the difference between the revenues collected under the existing rates and what water rates would have been using the 21% federal income tax rate now effective under the Tax Act. The accrued amounts for the period January 25, 2018 through April 30, 2018 were refunded along with the regular monthly Federal Tax Cut Credit (“FTCC”) on bills prepared during the month of June. The FTCC customer credit will continue to be reflected on customer bills every month until the implementation of new rates resulting from the next rate case. It is projected this credit will reduce water revenue by $1,023 in 2018 with no impact on after tax income.

Regulatory Rate Filings

On January 4, 2018, San Jose Water Company filed General Rate Case Application No. 18-01-004 with the CPUC requesting authority for an increase of revenue of $34,288, or 9.76%, in 2019, $14,232, or 3.70%, in 2020 and $20,582, or 5.17%, in 2021. Among other things, the application also includes requests to recover $20,725 from balancing and memorandum accounts, the establishment of a Water Revenue Adjustment Mechanism and Sales Reconciliation Mechanism, and a shift to greater revenue collection in the service charge. On June 28, 2018, the CPUC issued an order in the case identifying the issues to be considered, including whether the proposed merger between SJW Group and Connecticut Water Service, Inc. will have any ratemaking impact on the customers of San Jose Water Company (see discussion on the proposed merger at Note 12). The application is in a year-long review process and new rates, if approved, are expected to become effective January 1, 2019.

On March 14, 2018, San Jose Water Company filed Advice Letter No. 517 to update its Cost of Capital Memorandum Account, which tracks the difference between current water rates and those adopted in Decision 18-03-035. This was approved on April 4, 2018.

The CPUC directed its Class A water utilities, including San Jose Water Company, to reflect the changes to the Internal Revenue Code resulting from the passage of the Tax Act in customer rates. On May 8, 2018, the CPUC directed San Jose Water Company to file an advice letter to implement a change in water rates to reflect the lower income tax rate provided by the Tax Act, effective July 1, 2018. On May 23, 2018, San Jose Water Company filed Advice Letter No. 522 in compliance with the CPUC’s directive. On June 7, 2018, San Jose Water Company filed Advice Letter No. 522A amending the rate change to reflect a reduction in revenue requirement for 2018 of $14,801 or 3.89%, with no impact on after tax income. This request became effective July 1, 2018.

On June 13, 2018, San Jose Water Company filed Advice Letter No. 523 with the CPUC requesting authorization to implement surcharges to offset the increases to purchased potable water charges, the ground water extraction fee, and purchased recycled water charges implemented by the Santa Clara Valley Water District and South Bay Water Recycling effective July 1, 2018. The increases amount to a revenue increase of $13,732 or 3.75%. This request became effective July 1, 2018.

San Jose Water Company filed Advice Letter No. 524 with the CPUC on July 26, 2018, requesting authorization to recover the 2017 capital additions related to the Montevina Water Treatment Plant Upgrade Project. The filing requests a revenue increase of $3,155 or 0.83% and is anticipated to become effective on or about August 25, 2018, pending the CPUC’s approval.

The Public Utilities Commission of Texas (“PUCT”) directed CLWSC (as well as other Class A water utilities in Texas) to quantify all of the impacts of the passage of the Tax Act and make rate adjustments reflecting such impacts on a prospective basis. PUCT Order 47945-36 as amended by 47945-41 orders the water utilities to record a regulatory liability that reflects (1) the difference between the revenues collected under existing rates and the revenues that would have been collected had the existing rates been set using the recently approved federal income tax rates; and (2) the balance of excess accumulated deferred federal income taxes that now exists because of the decrease in the federal income tax rate from 35% to 21%. A rate proposal reflecting these tax changes was submitted for PUCT’s review on April 19, 2018.

CLWSC subsequently amended their filing on April 30, 2018 to update the customer notice, and to replace estimates for April with recorded April 2018 information. This filing will return to the ratepayers the difference between the revenues collected under the existing rates and what water rates would have been using the 21% federal income tax rate now effective under the Tax Act. The accrued amounts for the period January 25, 2018 through April 30, 2018 were refunded along with the regular monthly Federal Tax Cut Credit (“FTCC”) on bills prepared during the month of June. The FTCC customer credit will continue to be reflected on customer bills every month until the implementation of new rates resulting from the next rate case. It is projected this credit will reduce water revenue by $1,023 in 2018 with no impact on after tax income.