SJW (SJW) 10-Q 27 Jul 18 2018 Q2 Quarterly report Financial data

Document and Entity Information

Document and Entity Information Document - shares	6 Months Ended
	Jun. 30, 2018	Jul. 23, 2018
Document and Entity Information [Abstract]
Entity Registrant Name	SJW GROUP
Entity Central Index Key	766,829
Current Fiscal Year End Date	--12-31
Entity Filer Category	Large Accelerated Filer
Document Type	10-Q
Document Period End Date	Jun. 30, 2018
Document Fiscal Year Focus	2,018
Document Fiscal Period Focus	Q2
Amendment Flag	false
Entity Common Stock, Shares Outstanding		20,618,102

Condensed Consolidated Statemen

Condensed Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
REVENUE	$ 99,086	$ 102,073	$ 174,128	$ 171,118
Production Expenses:
Purchased water	23,712	22,181	39,128	36,105
Power	1,624	1,704	2,892	2,991
Groundwater extraction charges	9,919	10,932	19,451	18,342
Other production expenses	4,626	3,991	8,838	7,851
Total production expenses	39,881	38,808	70,309	65,289
Administrative and general	11,958	11,815	23,526	22,960
Maintenance	4,596	4,487	9,056	8,384
Property taxes and other non-income taxes	3,450	3,111	7,316	6,806
Depreciation and amortization	13,656	12,033	27,239	24,152
Merger related expenses	2,746	0	6,552	0
Total operating expense	76,287	70,254	143,998	127,591
OPERATING INCOME	22,799	31,819	30,130	43,527
OTHER (EXPENSE) INCOME:
Interest on long-term debt and other interest expense	(6,084)	(5,756)	(12,136)	(11,813)
Pension non-service cost	(595)	(1,032)	(1,178)	(1,907)
Unrealized gain (loss) on California Water Service Group stock	140	0	(527)	0
Loss on sale of California Water Service Group stock	0	0	(87)	0
Gain on sale of real estate investments	0	6,903	0	6,903
Other, net	679	614	1,442	1,077
Income before income taxes	16,939	32,548	17,644	37,787
Provision for income taxes	4,068	11,964	3,488	13,532
NET INCOME BEFORE NONCONTROLLING INTEREST	12,871	20,584	14,156	24,255
Less net income attributable to the noncontrolling interest	0	1,896	0	1,896
SJW GROUP NET INCOME	12,871	18,688	14,156	22,359
Other comprehensive income, net of tax:
Unrealized gain on investment	0	56	0	172
SJW GROUP COMPREHENSIVE INCOME	$ 12,871	$ 18,744	$ 14,156	$ 22,531
SJW GROUP EARNINGS PER SHARE
Basic (usd per share)	$ 0.63	$ 0.91	$ 0.69	$ 1.09
Diluted (usd per share)	0.62	0.90	0.68	1.08
DIVIDENDS PER SHARE (usd per share)	$ 0.28	$ 0.22	$ 0.56	$ 0.44
WEIGHTED AVERAGE SHARES OUTSTANDING
Basic (shares)	20,592,014	20,504,357	20,576,757	20,495,211
Diluted (shares)	20,732,127	20,673,775	20,716,665	20,664,556

Condensed Consolidated Balance

Condensed Consolidated Balance Sheets - USD ($) $ in Thousands	Jun. 30, 2018	Dec. 31, 2017
Utility plant:
Land	$ 18,212	$ 17,831
Depreciable plant and equipment	1,755,624	1,714,228
Construction in progress	68,153	45,851
Intangible assets	15,650	14,413
Utility plant, gross	1,857,639	1,792,323
Less accumulated depreciation and amortization	579,572	553,059
Utility plant, net	1,278,067	1,239,264
Real estate investments	56,336	56,213
Less accumulated depreciation and amortization	11,730	11,132
Total	44,606	45,081
CURRENT ASSETS:
Cash and cash equivalents	8,926	7,799
Accounts receivable:
Customers, net of allowances for uncollectible accounts	21,703	17,305
Income tax	2,252	7,981
Other	1,034	1,118
Accrued unbilled utility revenue	32,950	27,905
Other current assets	6,308	4,750
Current assets	73,173	66,858
OTHER ASSETS:
Investment in California Water Service Group	3,207	4,535
Net regulatory assets, less current portion	98,332	99,554
Other	2,736	2,709
Other assets	104,275	106,798
Assets	1,500,121	1,458,001
Stockholders’ equity:
Common stock, $0.001 par value; authorized 36,000,000 shares; issued and outstanding shares 20,594,486 on June 30, 2018 and 20,520,856 on December 31, 2017	21	21
Additional paid-in capital	84,375	84,866
Retained earnings	380,898	376,119
Accumulated other comprehensive income	0	2,203
Total stockholders’ equity	465,294	463,209
Long-term debt, less current portion	431,258	431,092
Capitalization, Long-term Debt and Equity	896,552	894,301
CURRENT LIABILITIES:
Line of credit	59,000	25,000
Accrued groundwater extraction charges, purchased water and power	18,555	14,382
Accounts payable	26,183	22,960
Accrued interest	6,968	6,869
Accrued property taxes and other non-income taxes	971	1,904
Accrued payroll	4,837	6,011
Other current liabilities	8,037	7,926
Current liabilities	124,551	85,052
DEFERRED INCOME TAXES	84,064	85,795
ADVANCES FOR CONSTRUCTION	80,993	83,695
CONTRIBUTIONS IN AID OF CONSTRUCTION	164,122	160,830
POSTRETIREMENT BENEFIT PLANS	75,229	72,841
REGULATORY LIABILITY	61,639	62,476
OTHER NONCURRENT LIABILITIES	12,971	13,011
COMMITMENTS AND CONTINGENCIES	0	0
Capitalization and liabilities	$ 1,500,121	$ 1,458,001

Condensed Consolidated Balance4

Condensed Consolidated Balance Sheets (Parenthetical) - $ / shares	Jun. 30, 2018	Dec. 31, 2017
Statement of Financial Position [Abstract]
Common stock, par value (usd per share)	$ 0.001	$ 0.001
Common stock, shares authorized (shares)	36,000,000	36,000,000
Common stock, shares issued (shares)	20,594,486	20,520,856
Common stock, shares outstanding (shares)	20,594,486	20,520,856

Condensed Consolidated Stateme5

Condensed Consolidated Statements of Cash Flows - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017
OPERATING ACTIVITIES:
Net income before noncontrolling interest	$ 14,156	$ 24,255
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	28,389	25,258
Deferred income taxes	(2,129)	1,286
Stock-based compensation	879	1,044
Unrealized loss on California Water Service Group stock	527	0
Gain on sale of real estate investments	0	(6,903)
Loss on sale of California Water Service Group stock	87	0
Changes in operating assets and liabilities:
Accounts receivable and accrued unbilled utility revenue	(9,359)	(7,814)
Accounts payable and other current liabilities	1,414	725
Accrued groundwater extraction charges, purchased water and power	4,173	7,376
Tax payable and receivable, and other accrued taxes	5,607	12,030
Postretirement benefits	2,388	2,651
Regulatory assets and liability related to balancing and memorandum accounts	1,399	(3,031)
Other changes, net	(2,105)	114
NET CASH PROVIDED BY OPERATING ACTIVITIES	45,426	56,991
INVESTING ACTIVITIES:
Company-funded	(62,091)	(60,921)
Contributions in aid of construction	(3,091)	(4,258)
Additions to real estate investments	(123)	(119)
Payments to retire utility plant, net of salvage	(2,787)	(718)
Proceeds from sale of real estate investments	0	11,180
Proceeds from sale of California Water Service Group stock	714	0
Payments for business/asset acquisition and water rights	0	1,150
Deposit for long-lived asset held-for-sale	0	3,000
NET CASH USED IN INVESTING ACTIVITIES	(67,378)	(52,986)
FINANCING ACTIVITIES:
Borrowings on line of credit	34,000	2,500
Repayments of line of credit	0	(16,700)
Repayments of long-term borrowings	0	(2,717)
Payment to noncontrolling interest	0	(1,896)
Dividends paid	(11,520)	(8,916)
Receipts of advances and contributions in aid of construction	4,560	9,052
Refunds of advances for construction	(1,251)	(1,202)
Other changes, net	(2,710)	(248)
NET CASH PROVIDED BY (USED IN) FINANCING ACTIVITIES	23,079	(20,127)
NET CHANGE IN CASH AND CASH EQUIVALENTS	1,127	(16,122)
CASH AND CASH EQUIVALENTS, BEGINNING OF PERIOD	7,799	25,350
CASH AND CASH EQUIVALENTS, END OF PERIOD	8,926	9,228
Cash paid during the period for:
Interest	13,240	12,382
Income taxes	420	237
Supplemental disclosure of non-cash activities:
Change in accrued payables for construction costs capitalized	1,657	7,985
Utility property installed by developers	$ 565	$ 381

General

General	6 Months Ended
	Jun. 30, 2018
Organization, Consolidation and Presentation of Financial Statements [Abstract]
GENERAL	General In the opinion of management, the accompanying unaudited condensed consolidated financial statements reflect all adjustments (consisting only of normal, recurring adjustments) necessary for a fair presentation of the results for the interim periods. The unaudited interim financial information has been prepared in accordance with accounting principles generally accepted in the United States of America (“GAAP”) and in accordance with the instructions for Form 10-Q and Rule 10-01 of Regulation S-X promulgated by the Securities and Exchange Commission (the “SEC”). The Notes to Consolidated Financial Statements in SJW Group’s 2017 Annual Report on Form 10-K should be read with the accompanying unaudited condensed consolidated financial statements. Recently Adopted Accounting Pronouncements In May 2014, the Financial Accounting Standards Board (“FASB”) issued Accounting Standard Update (“ASU”) 2014-09, “Revenue from Contracts with Customers.” The core principle of the guidance is that an entity should recognize revenue to depict the transfer of promised goods or services to customers in an amount that reflects the consideration to which the entity expects to be entitled in exchange for those goods or services. The new standard replaced most existing revenue recognition guidance in generally accepted accounting principles. The updated guidance also requires additional disclosures regarding the nature, timing and uncertainty of revenue transactions. SJW Group adopted the new revenue standard on January 1, 2018, using the modified retrospective method, and determined that no adjustment to the opening balance of retained earnings was necessary for contracts with remaining obligations as of the effective date. In addition, SJW Group applied the “right to invoice” practical expedient. The adoption of the new standard requires certain changes to the recognition of balancing and memorandum account revenue and related costs (See Note 9, “Balancing and Memorandum Accounts”). However, the changes did not have a material impact on our consolidated results of operations, financial position, or cash flows. Concurrently, the company implemented ASU 2017-10, “Identifying the Customer in a Service Concession Arrangement.” Upon adoption of ASU 2017-10, the service concession fee paid to the City of Cupertino was determined to be an up-front payment and accordingly will be amortized as a reduction to future revenue as opposed to amortized as an expense on SJW Group’s Consolidated Statements of Comprehensive Income. In January 2016, the FASB issued ASU 2016-01, “Financial Instruments - Overall” which changes the recognition of changes in fair value of financial liabilities when the fair value option is elected. In addition, the standard requires equity investments to be measured at fair value with changes in fair value recognized in net income instead of through other comprehensive income. The updated guidance affects the accounting for the company’s equity investment in California Water Service Group stock classified as an available-for-sale security (see Note 7 and Note 11 of “Notes to Unaudited Consolidated Financial Statements”). The new standard became effective for SJW Group beginning in the first quarter of the fiscal year ending December 31, 2018. Prior to adoption of ASU 2016-01, SJW Group recognized changes in fair value of its equity investment in California Water Service Group stock through other comprehensive income or loss on the statement of comprehensive income. Upon adoption on January 1, 2018, SJW Group began recording the change in fair value of its equity investment in other income and expense. In addition, the ASU stated that entities should apply the new standard by means of a cumulative-effect adjustment to the balance sheet as of the beginning of the fiscal year of adoption. As such, SJW Group recorded a cumulative-effect adjustment of $2,203 to beginning retained earnings to eliminate the cumulative change in fair value of its equity investment, net of tax from accumulated other comprehensive income. In October 2016, the FASB issued ASU 2016-16, “Intra-Entity Transfers of Assets Other Than Inventory,” which modifies existing guidance and is intended to reduce diversity in practice with respect to accounting for the income tax consequences of intra-entity transfers of assets. The ASU requires that the current and deferred income tax consequences of intra-entity transfers of assets be immediately recognized. Prior guidance allowed the entities to defer the consolidated tax consequences of an intercompany transfer of an asset other than inventory to a future period and amortize those tax consequences over time. SJW Group adopted ASU 2016-16 effective January 1, 2018. As SJW Group did not have any unamortized tax expense, the company did not have any cumulative catch-up adjustments upon adoption of this ASU. In March 2017, the FASB issued ASU 2017-07, “Improving the Presentation of Net Periodic Pension Cost and Net Periodic Postretirement Benefit Costs,” which requires employers to present the service cost component of the net periodic benefit cost in the same income statement line item as other employee compensation costs arising from services rendered during the period. The standard provides that only the service cost component of net periodic pension costs is eligible for asset capitalization. Companies should present the other components of net periodic benefit costs separately from the line items that include the service cost and outside of any subtotal of operating income, if one is presented. ASU 2017-07 requires retrospective presentation in the income statement of the service cost component and the other components of net periodic cost and net periodic postretirement benefit cost and prospective presentation from date of adoption for the capitalization in assets of only the service cost component of net periodic cost and net periodic postretirement benefit cost. SJW Group adopted ASU 2017-07 effective January 1, 2018. As such, the consolidated statements of comprehensive income for the periods presented have been reclassified to reflect the retrospective changes. See Note 4 of “Defined Benefit Plan” for further discussion. Revenue Water sales are seasonal in nature and influenced by weather conditions. The timing of precipitation and climatic conditions can cause seasonal water consumption by customers to vary significantly. Due to the seasonal nature of the water business, the operating results for interim periods are not indicative of the operating results for a 12-month period. Revenue is generally higher in the warm, dry summer months when water usage and sales are greater, and lower in the winter months when cooler temperatures and increased rainfall curtail water usage and sales. On January 1, 2018, SJW Group adopted FASB ASC Topic 606 - “Revenue from Contracts with Customers.” In accordance with Topic 606, management has determined that the company has principally four categories of revenues. The first category, revenue from contracts with customers, represents metered revenue of Water Utility Services which includes billings to customers based on meter readings plus an estimate of water used between the customers’ last meter reading and the end of the accounting period. SJW Group satisfies its performance obligation upon delivery of water to the customer at which time the customer consumes the benefits provided by the company. The customer is typically billed on a bi-monthly basis after water delivery has occurred. The customer is charged both a service charge which is based upon meter size and covers a portion of the fixed costs of furnishing water to the customer and a consumption charge based on actual water usage. Unbilled revenue from the last meter reading date to the end of the accounting period is estimated based on the most recent usage patterns, production records and the effective tariff rates. As the company has the right to bill for services that it has provided, SJW Group estimates the dollar value of deliveries during the unbilled period and recognizes the associated revenue. Actual results could differ from those estimates, which may result in an adjustment to revenue when billed in a subsequent period. The second category, rental income, represents lease rental income from SJW Land Company tenants. The tenants pay monthly in accordance with lease agreements and SJW Group recognizes the income ratably over the lease term as this is the most representative of the pattern in which the benefit is expected to be derived from SJW Group’s underlying asset. The third and fourth revenue categories are other balancing and memorandum accounts and alternative revenue programs. Both are scoped out of Topic 606 and are accounted for under FASB ASC Topic 980 - “Regulated Operations.” Balancing and memorandum accounts are recognized by San Jose Water Company when it is probable that future recovery of previously incurred costs or future refunds that are to be credited to customers will occur through the ratemaking process. In addition, in the case of special revenue programs such as the Water Conservation Memorandum Account (“WCMA”), San Jose Water Company follows the requirements of ASC Topic 980-605-25, “Alternative Revenue Programs” in determining revenue recognition, including the requirement that such revenues will be collected within 24 months of the year-end in which the revenue is recorded. A reserve is recorded for amounts SJW Group estimates will not be collected within the 24-month period. This reserve is based on an estimate of actual usage over the recovery period, offset by applicable drought surcharges. In assessing the probability criteria for balancing and memorandum accounts between general rate cases, San Jose Water Company considers evidence that may exist prior to California Public Utilities Commission (“CPUC”) authorization that would satisfy ASC Topic 980 subtopic 340-25 recognition criteria. Such evidence may include regulatory rules and decisions, past practices, and other facts and circumstances that would indicate that recovery or refund is probable. When such evidence provides sufficient support, the balances are recorded in SJW Group’s financial statements. From 2014 to 2016, California was in a severe drought. In response to the drought, the State Water Resources Control Board (the “State Water Board”) imposed mandatory water use restrictions and conservation targets. The Santa Clara Valley Water District (“SCVWD”), San Jose Water Company’s principal water supplier, also mandated water use restrictions along with conservation targets at levels higher than the State Water Board. While the Governor of California declared the drought over on April 7, 2017, the State Water Board made certain water use restrictions permanent while SCVWD maintained a conservation target at 20% . On May 31, 2018, Governor Edmund G. Brown signed into law Assembly Bill 1668 and Senate Bill 606. Both bills set an initial limit for indoor water use of 55 gallons per person per day by 2022 and reduced the limit further to 50 gallons per person per day by 2030. Implementation details remain to be developed as to how local water providers will meet this mandate as well as to how the CPUC will direct its regulated utilities to comply. To encourage conservation, San Jose Water Company received approval from the CPUC to implement a Mandatory Conservation Revenue Adjustment Memorandum Account in 2014. This account was subsequently replaced with a WCMA. The WCMA allows San Jose Water Company to track lost revenue, net of related water costs, associated with reduced sales due to water conservation and associated calls for water use reductions. San Jose Water Company records the lost revenue captured in the WCMA regulatory accounts once the revenue recognition requirements of FASB ASC Topic 980 - “Regulated Operations,” subtopic 605-25 are met. For further discussion, please see Note 8 and Note 9. The major streams of revenue for SJW Group are as follows: Three months ended June 30, Six months ended June 30, 2018 2017 2018 2017 Revenue from contracts with customers $ 98,443 95,857 $ 174,312 164,424 Alternative revenue programs, net - WCMA 3,933 7,639 3,601 9,915 Other balancing and memorandum accounts revenue, net * (4,611 ) (2,750 ) (6,447 ) (6,111 ) Rental income 1,321 1,327 2,662 2,890 $ 99,086 102,073 $ 174,128 171,118 * The amount reflected for three and six months ended June 30, 2018 , excludes a further addition of $1,351 and $1,030 , respectively, to revenue related to cost-recovery balancing accounts which upon adoption of Topic 606 are recorded as capitalized costs until recovery is approved by the CPUC. During 2017, prior to adoption of Topic 606, these amounts were recorded as revenue. For further discussion, please see Note 9. Income Taxes On December 22, 2017, the Tax Cuts and Jobs Act (H.R. 1) (the “Tax Act”) was signed into law. Among other things, the Tax Act permanently lowers the corporate statutory tax rate to 21% from the previous maximum rate of 35% , effective for tax years including or commencing January 1, 2018. See Note 8 and Note 9, for discussion on the effect of the Tax Act on SJW Group’s regulatory activities. Earnings per Share Basic earnings per share is calculated using income available to common stockholders, divided by the weighted average number of shares outstanding during the period. Diluted earnings per share is calculated using income available to common stockholders divided by the weighted average number of shares of common stock including both shares outstanding and shares potentially issuable in connection with deferred restricted common stock awards under SJW Group’s Long-Term Incentive Plan (as amended, the “Incentive Plan”) and shares potentially issuable under the Employee Stock Purchase Plan (“ESPP”). For the three months ended June 30, 2018 and 2017 , 2,094 and 981 anti-dilutive restricted common stock units were excluded from the dilutive earnings per share calculation, respectively. For the six months ended June 30, 2018 , and 2017 , 3,256 and 2,987 anti-dilutive restricted common stock units were excluded from the dilutive earnings per share calculation, respectively. Utility Plant Depreciation A portion of depreciation expense is allocated to administrative and general expense. For the three months ended June 30, 2018 and 2017 , the amounts allocated to administrative and general expense were $572 and $579 , respectively. For the six months ended June 30, 2018 , and 2017 , the amounts allocated to administrative and general expense were $1,150 and $1,106 , respectively.

Equity Plans

Equity Plans	6 Months Ended
	Jun. 30, 2018
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
EQUITY PLANS	Equity Plans SJW Group accounts for stock-based compensation based on the grant date fair value of awards issued to employees in accordance with FASB ASC Topic 718 - “Compensation - Stock Compensation,” which requires the measurement and recognition of compensation expense based on estimated fair value for stock-based payment awards. The Incentive Plan allows SJW Group to provide employees, non-employee board members or the board of directors of any parent or subsidiary, consultants, and other independent advisors who provide services to the company or any parent or subsidiary the opportunity to acquire an equity interest in SJW Group. The types of awards included in the Incentive Plan are restricted stock awards, restricted stock units, performance stock units, or other stock-based awards. As of June 30, 2018 , the remaining number of shares available under the Incentive Plan was 881,914 , and an additional 190,405 shares were issuable under outstanding restricted stock units and deferred restricted stock units. In addition, shares are issued to employees under the company’s ESPP. Stock compensation costs charged to income are recognized on a straight-line basis over the requisite service period. A summary of compensation costs charged to income, proceeds from the exercise of stock options and similar instruments, and the tax benefit realized from stock options and similar instruments exercised, that were recorded to additional paid-in capital and common stock, by award type, are presented below for the three and six months ended June 30, 2018 , and 2017 . Three months ended June 30, Six months ended June 30, 2018 2017 2018 2017 Adjustments to additional paid-in capital and common stock for: Compensation costs charged to income: ESPP $ — — $ 115 100 Restricted stock and deferred restricted stock 392 458 764 944 Total compensation costs charged to income $ 392 458 $ 879 1,044 Proceeds from ESPP $ — — $ 653 570 Stock, Restricted Stock and Deferred Restricted Stock On January 2, 2018 , service-based restricted stock units covering an aggregate of 12,296 shares of common stock of SJW Group were granted to certain officers of SJW Group and its subsidiaries. The units vest in three equal successive installments upon completion of each year of service with no dividend equivalent rights. Share-based compensation expense of $60.22 per unit which was based on the award grant date fair value is being recognized over the service period beginning in 2018. On January 30, 2018 , certain officers of SJW Group were granted performance-based restricted stock units covering an aggregate target number of SJW Group’s shares of common stock equal to 4,081 that will vest based on the actual attainment of specified performance goals measured for the 2018 calendar year and continued service through December 31, 2018. The number of shares issuable under such units, ranging between 0% to 150% of the target number of shares, is based on the level of actual attainment of specified performance goals. The units do not include dividend equivalent rights. The awards have no market conditions and the stock-based compensation expense of $58.02 per unit which was based on the award grant date fair value is being recognized assuming the performance goals will be attained. As of June 30, 2018 , management believes it is probable that the performance goals will be met. On January 30, 2018 , certain officers of SJW Group were granted performance-based restricted stock units covering an aggregate target number of SJW Group’s shares of common stock equal to 5,259 that will vest based on the actual attainment of specified performance goals for the 2020 calendar year and continued service through December 31, 2020. The number of shares issuable under the awards, ranging between 0% to 150% of the target number of shares, is based on the level of actual attainment of specified performance goals. The units do not include dividend equivalent rights. The awards have no market conditions and the stock-based compensation expense of $55.89 per unit which is based on the award grant date fair value is being recognized assuming the performance goals will be attained. As of June 30, 2018 , management believes that it is probable that the performance goals will be met. On January 30, 2018 , performance-based restricted stock units were granted to an officer of SJW Group covering a target number of shares of SJW Group’s common stock equal to 6,342 that will vest based on continued service and attainment of specified performance goals over the period from January 1, 2018, to December 31, 2020. The number of shares issuable under the award, ranging between 0% and 200% of the target number of shares, is based on the level of actual attainment of specified performance goals. These units do not include dividend equivalent rights. The fair value of the performance-based restricted stock award was estimated utilizing the Monte Carlo valuation model, using the fair value of SJW Group’s common stock with the effect of market conditions and no dividend yield on the date of grant, and assumes the performance goals will be attained. Stock-based compensation expense is recognized at $63.85 per unit. If such goals are not met and requisite service is not rendered, no compensation cost will be recognized and any recognized compensation cost will be reversed. On April 25, 2018 , restricted stock units covering an aggregate of 7,385 shares of common stock of SJW Group were granted to the non-employee board members of SJW Group. The units vest upon continuous board service through the day immediately preceding the date of the next annual stockholder meeting with no dividend equivalent rights. Stock-based compensation expense of $55.80 per unit, which is based on the award grant date fair value, is being recognized over the service period beginning in 2018. As of June 30, 2018 , the total unrecognized compensation costs related to restricted and deferred restricted stock plans was $2,462 . This cost is expected to be recognized over a remaining weighted average period of 1.59 years. Employee Stock Purchase Plan The ESPP allows eligible employees to purchase shares of SJW Group’s common stock at 85% of the fair value of shares on the purchase date. Under the ESPP, employees can designate up to a maximum of 10% of their base compensation for the purchase of shares of common stock, subject to certain restrictions. A total of 400,000 shares of common stock were reserved for issuance under the ESPP. SJW Group’s recorded expenses were $62 and $132 for the three and six months ended June 30, 2018 , respectively, and $54 and $117 for the three and six months ended June 30, 2017 , respectively, related to the ESPP. The total unrecognized compensation costs related to the semi-annual offering period that ends July 31, 2018 , for the ESPP is approximately $23 . This cost is expected to be recognized during the third quarter of 2018.

Real Estate Investments

Real Estate Investments	6 Months Ended
	Jun. 30, 2018
Real Estate Investments, Net [Abstract]
REAL ESTATE INVESTMENTS	Real Estate Investments The major components of real estate investments as of June 30, 2018 , and December 31, 2017 , are as follows: June 30, December 31, Land $ 13,262 13,262 Buildings and improvements 43,074 42,951 Subtotal 56,336 56,213 Less: accumulated depreciation and amortization 11,730 11,132 Total $ 44,606 45,081 Depreciation and amortization is computed using the straight-line method over the estimated useful lives of the assets, ranging from 7 to 39 years . On April 6, 2017, 444 West Santa Clara Street, L.P. sold all of its interests in the commercial building and land the partnership owned and operated for $11,000 . 444 West Santa Clara Street, L.P. recognized a pre-tax gain on sale of real estate investments of $6,323 , after selling expenses of $1,157 . SJW Land Company holds a 70% limited interest in 444 West Santa Clara Street, L.P. SJW Land Company and the noncontrolling interest recognized a pre-tax gain on sale of real estate investments of $4,427 and $1,896 , respectively, on the transaction. In addition, SJW Land Company sold undeveloped land located in San Jose, California for $1,350 on April 6, 2017. SJW Land Company recognized a pre-tax gain on sale of real estate investments of $580 on the transaction, after selling expenses of $14 .

Defined Benefit Plan

Defined Benefit Plan	6 Months Ended
	Jun. 30, 2018
Retirement Benefits [Abstract]
DEFINED BENEFIT PLAN	Defined Benefit Plan San Jose Water Company sponsors a noncontributory defined benefit pension plan for its eligible employees. Employees hired before March 31, 2008, are entitled to receive retirement benefits using a formula based on the employee’s three highest years of compensation (whether or not consecutive). For employees hired on or after March 31, 2008, benefits are determined using a cash balance formula based on compensation credits and interest credits for each employee. Officers hired before March 31, 2008, are eligible to receive additional retirement benefits under the Executive Supplemental Retirement Plan, and officers hired on or after March 31, 2008, are eligible to receive additional retirement benefits under the Cash Balance Executive Supplemental Retirement Plan. Both plans are non-qualified plans in which only officers and other designated members of management may participate. San Jose Water Company also provides health care and life insurance benefits for retired employees under the San Jose Water Company Social Welfare Plan. The components of net periodic benefit costs for San Jose Water Company’s pension plan, its Executive Supplemental Retirement Plan, Cash Balance Executive Supplemental Retirement Plan and Social Welfare Plan for the three and six months ended June 30, 2018 , and 2017 are as follows: Three months ended June 30, Six months ended June 30, 2018 2017 2018 2017 Service cost $ 1,607 1,288 $ 3,203 2,614 Interest cost 1,876 1,920 3,753 3,823 Other cost 1,145 1,165 2,278 2,203 Expected return on assets (2,426 ) (2,053 ) (4,853 ) (4,119 ) $ 2,202 2,320 $ 4,381 4,521 Effective January 1, 2018, SJW Group adopted ASU 2017-07, “Improving the Presentation of Net Periodic Pension Cost and Net Periodic Postretirement Benefit Costs.” The new standard requires retrospective presentation in the income statement of the service cost component and the other components of net periodic pension cost and net periodic postretirement benefit cost and prospective presentation from date of adoption for the capitalization in assets of only the service cost component of net periodic pension cost and net periodic postretirement benefit cost. As of June 30, 2017 , utility plant included $265 of pension non-service cost in utility plant. The components of net periodic benefit cost have been recorded in the consolidated statements of comprehensive income as follows: Three months ended June 30, Six months ended June 30, 2018 2017 2018 2017 Other production expenses $ 426 336 $ 849 685 Administrative and general expense 902 723 1,797 1,464 Maintenance expense 279 229 557 465 Pension non-service costs 595 1,032 1,178 1,907 $ 2,202 2,320 $ 4,381 4,521 The following tables summarize the fair values of plan assets by major categories as of June 30, 2018 , and December 31, 2017 : Fair Value Measurements at June 30, 2018 Quoted Prices in Active Markets for Identical Assets Significant Observable Inputs Significant Unobservable Inputs Asset Category Benchmark Total (Level 1) (Level 2) (Level 3) Cash and cash equivalents — $ 5,309 $ 5,309 $ — $ — Actively Managed (a): All Cap Equity Russell 3000 Value 6,450 6,408 42 — U.S. Large Cap Equity Russell 1000, Russell 1000 Growth, Russell 1000 Value 52,125 52,125 — — U.S. Mid Cap Equity Russell Mid Cap, Russell Mid Cap Growth, Russell Mid Cap Value 9,628 9,628 — — U.S. Small Cap Equity Russell 2000, Russell 2000 Growth, Russell 2000 Value 9,805 9,805 — — Non-U.S. Large Cap Equity MSCI EAFE 5,759 5,759 — — REIT NAREIT - Equity REIT’S 6,276 — 6,276 — Fixed Income (b) (b) 45,153 — 45,153 — Total $ 140,505 $ 89,034 $ 51,471 $ — The Plan has a current target allocation of 55% invested in a diversified array of equity securities to provide long-term capital appreciation and 45% invested in a diversified array of fixed income securities and cash to provide preservation of capital plus generation of income. (a) Actively managed portfolio of securities with the goal to exceed the stated benchmark performance. (b) Actively managed portfolio of fixed income securities with the goal to exceed the Barclays 1-5 Year Government/Credit, Barclays Intermediate Government/Credit, and Merrill Lynch Preferred Stock Fixed Rate. Fair Value Measurements at December 31, 2017 Quoted Prices in Active Markets for Identical Assets Significant Observable Inputs Significant Unobservable Inputs Asset Category Benchmark Total (Level 1) (Level 2) (Level 3) Cash and cash equivalents — $ 8,207 $ 8,207 $ — $ — Actively Managed (a): All Cap Equity Russell 3000 Value 6,413 6,376 37 — U.S. Large Cap Equity Russell 1000, Russell 1000 Growth, Russell 1000 Value 50,351 50,351 — — U.S. Mid Cap Equity Russell Mid Cap, Russell Mid Cap Growth, Russell Mid Cap Value 9,358 9,358 — — U.S. Small Cap Equity Russell 2000, Russell 2000 Growth, Russell 2000 Value 8,725 8,725 — — Non-U.S. Large Cap Equity MSCI EAFE 5,973 5,973 — — REIT NAREIT - Equity REIT’S 6,143 — 6,143 — Fixed Income (b) (b) 44,994 — 44,994 — Total $ 140,164 $ 88,990 $ 51,174 $ — The Plan has a current target allocation of 55% invested in a diversified array of equity securities to provide long-term capital appreciation and 45% invested in a diversified array of fixed income securities and cash to provide preservation of capital plus generation of income. (a) Actively managed portfolio of securities with the goal to exceed the stated benchmark performance. (b) Actively managed portfolio of fixed income securities with the goal to exceed the Barclays 1-5 Year Government/Credit, Barclays Intermediate Government/Credit, and Merrill Lynch Preferred Stock Fixed Rate. In 2018 , San Jose Water Company expects to make required and discretionary cash contributions of up to $7,450 to the pension plans and Social Welfare Plan. For the three and six months ended June 30, 2018 , $1,420 has been contributed to the pension plans and Social Welfare Plan.

Segment and Non-Tariffed Busine

Segment and Non-Tariffed Business Reporting	6 Months Ended
	Jun. 30, 2018
Segment Reporting [Abstract]
SEGMENT AND NONTARIFFED BUSINESS REPORTING	Segment and Non-Tariffed Business Reporting SJW Group is a holding company with four subsidiaries: (i) San Jose Water Company, a water utility which operates both regulated and non-tariffed businesses, (ii) SJWTX, Inc. which is doing business as Canyon Lake Water Service Company (“CLWSC”), a regulated water utility located in Canyon Lake, Texas, and its consolidated non-tariffed variable interest entity, Acequia Water Supply Corporation, (iii) SJW Land Company and its consolidated variable interest entity, 444 West Santa Clara Street, L.P., which operated a commercial building rental that was sold in April 2017, and (iv) Hydro Sub, Inc., a Connecticut corporation that was formed on March 9, 2018 for the sole purpose of effecting the SJW Group and Connecticut Water Service, Inc. (“CTWS”) proposed merger (see discussion on the proposed merger at Note 12). In November 2017, SJW Group sold all its equity interest in Texas Water Alliance Limited, a non-tariffed water utility operation which had acquired permits and leases necessary to develop a water supply project in Texas. In accordance with FASB ASC Topic 280 - “Segment Reporting,” SJW Group has determined that it has two reportable business segments. The first segment is that of providing water utility and utility-related services to its customers through SJW Group’s subsidiaries, San Jose Water Company, CLWSC, and Texas Water Alliance Limited (up to November 2017), together referred to as “Water Utility Services.” The second segment is property management and investment activity conducted by SJW Land Company, referred to as “Real Estate Services.” SJW Group’s reportable segments have been determined based on information used by the chief operating decision maker. SJW Group’s chief operating decision maker includes the Chairman, President and Chief Executive Officer, and his senior staff. The senior staff reviews financial information presented on a consolidated basis that is accompanied by disaggregated information about operating revenue, net income and total assets, by subsidiaries. The following tables set forth information relating to SJW Group’s reportable segments and distribution of regulated and non-tariffed business activities within the reportable segments. Certain allocated assets, revenue and expenses have been included in the reportable segment amounts. Other business activity of SJW Group not included in the reportable segments is included in the “All Other” category. For Three Months Ended June 30, 2018 Water Utility Services Real Estate Services All Other* SJW Group Regulated Non-tariffed Non-tariffed Non-tariffed Regulated Non-tariffed Total Operating revenue $ 95,798 1,967 1,321 — 95,798 3,288 99,086 Operating expense 70,642 1,278 891 3,476 70,642 5,645 76,287 Operating income (loss) 25,156 689 430 (3,476 ) 25,156 (2,357 ) 22,799 Net income (loss) before noncontrolling interest 15,022 497 296 (2,944 ) 15,022 (2,151 ) 12,871 Depreciation and amortization 13,272 85 299 — 13,272 384 13,656 Senior note and other interest expense 5,540 — — 544 5,540 544 6,084 Income tax expense (benefit) in net income 4,650 193 92 (867 ) 4,650 (582 ) 4,068 Assets $ 1,449,714 3,768 46,756 (117 ) 1,449,714 50,407 1,500,121 For Three Months Ended June 30, 2017 Water Utility Services Real Estate Services All Other* SJW Group Regulated Non-tariffed Non-tariffed Non-tariffed Regulated Non-tariffed Total Operating revenue $ 98,836 1,910 1,327 — 98,836 3,237 102,073 Operating expense 67,285 1,223 942 804 67,285 2,969 70,254 Operating income (loss) 31,551 687 385 (804 ) 31,551 268 31,819 Net income (loss) before noncontrolling interest 16,080 320 5,321 (1,137 ) 16,080 4,504 20,584 Depreciation and amortization 11,592 142 299 — 11,592 441 12,033 Senior note, mortgage and other interest expense 5,215 — (3 ) 544 5,215 541 5,756 Income tax expense (benefit) in net income 9,908 236 1,988 (168 ) 9,908 2,056 11,964 Assets $ 1,398,567 19,358 49,337 3,924 1,398,567 72,619 1,471,186 For Six Months Ended June 30, 2018 Water Utility Services Real Estate Services All Other* SJW Group Regulated Non-tariffed Non-tariffed Non-tariffed Regulated Non-tariffed Total Operating revenue $ 168,151 3,315 2,662 — 168,151 5,977 174,128 Operating expense 132,343 2,166 1,740 7,749 132,343 11,655 143,998 Operating income (loss) 35,808 1,149 922 (7,749 ) 35,808 (5,678 ) 30,130 Net income (loss) 19,817 828 652 (7,141 ) 19,817 (5,661 ) 14,156 Depreciation and amortization 26,473 168 598 — 26,473 766 27,239 Senior note and other interest expense 11,048 — — 1,088 11,048 1,088 12,136 Income tax expense (benefit) in net income 5,142 322 186 (2,162 ) 5,142 (1,654 ) 3,488 Assets $ 1,449,714 3,768 46,756 (117 ) 1,449,714 50,407 1,500,121 For Six Months Ended June 30, 2017 Water Utility Services Real Estate Services All Other* SJW Group Regulated Non-tariffed Non-tariffed Non-tariffed Regulated Non-tariffed Total Operating revenue $ 165,054 3,174 2,890 — 165,054 6,064 171,118 Operating expense 122,031 2,054 1,890 1,616 122,031 5,560 127,591 Operating income (loss) 43,023 1,120 1,000 (1,616 ) 43,023 504 43,527 Net income (loss) 20,029 492 5,681 (1,947 ) 20,029 4,226 24,255 Depreciation and amortization 23,252 278 622 — 23,252 900 24,152 Senior note, mortgage and other interest expense 10,640 — 62 1,111 10,640 1,173 11,813 Income tax expense (benefit) in net income 11,701 373 2,116 (658 ) 11,701 1,831 13,532 Assets $ 1,398,567 19,358 49,337 3,924 1,398,567 72,619 1,471,186 * The “All Other” category includes the accounts of SJW Group and Hydro Sub, Inc. on a stand-alone basis. For the six months ended June 30, 2018 , Hydro Sub, Inc. had no recorded revenue or expenses and as of June 30, 2018 , held no assets and had incurred no liabilities. For the six months ended June 30, 2017 , the “All Other” category includes the accounts of SJW Group on a stand-alone basis.

Long-Term Liabilities and Bank

Long-Term Liabilities and Bank Borrowings	6 Months Ended
	Jun. 30, 2018
Debt Disclosure [Abstract]
Long-Term Liabilities and Bank Borrowings	Long-Term Liabilities and Bank Borrowings SJW Group’s contractual obligations and commitments include senior notes, mortgages and other obligations. San Jose Water Company, a subsidiary of SJW Group, has received advance deposit payments from its customers on certain construction projects. Refunds of the advance deposit payments constitute an obligation of San Jose Water Company solely.

Fair Value Measurement

Fair Value Measurement	6 Months Ended
	Jun. 30, 2018
Fair Value Disclosures [Abstract]
FAIR VALUE MEASUREMENT	Fair Value Measurement The following instruments are not measured at fair value on SJW Group’s condensed consolidated balance sheets as of June 30, 2018 , but require disclosure of their fair values: cash and cash equivalents, accounts receivable and accounts payable. The estimated fair value of such instruments as of June 30, 2018 , approximates their carrying value as reported on the condensed consolidated balance sheets. The fair value of such financial instruments is determined using the income approach based on the present value of estimated future cash flows. There have been no changes in valuation techniques during the three and six months ended June 30, 2018 . The fair value of these instruments would be categorized as Level 2 in the fair value hierarchy, with the exception of cash and cash equivalents, which would be categorized as Level 1. The fair value of pension plan assets is discussed in Note 4. The fair value of SJW Group’s long-term debt was approximately $492,886 and $537,840 as of June 30, 2018 , and December 31, 2017 , respectively, and was determined using a discounted cash flow analysis, based on the current rates for similar financial instruments of the same duration and creditworthiness of the company. The book value of the long-term debt was $ 431,258 and $ 431,092 as of June 30, 2018 , and December 31, 2017 , respectively. The fair value of long-term debt would be categorized as Level 2 in the fair value hierarchy. As of June 30, 2018 , and December 31, 2017 , the fair value of the company’s investment in California Water Service Group was $3,207 and $4,535 , respectively, and would be categorized as Level 1 of the fair value hierarchy. For the three and six months ended June 30, 2018 , SJW Group recognized an unrealized gain of $140 and an unrealized loss of $527 , respectively, due to the change in fair value of the company’s investment in California Water Service Group.

Regulatory Rate Filings

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.

Balancing and Memorandum Accoun

Balancing and Memorandum Account Recovery Procedures	6 Months Ended
	Jun. 30, 2018
Regulated Operations [Abstract]
BALANCING AND MEMORANDUM ACCOUNT RECOVERY PROCEDURES	Balancing and Memorandum Accounts San Jose Water Company has established balancing accounts for the purpose of tracking the under-collection or over-collection associated with expense changes and the revenue authorized by the CPUC to offset those expense changes. San Jose Water Company also maintains memorandum accounts to track revenue impacts due to catastrophic events, certain unforeseen water quality expenses related to new federal and state water quality standards, energy efficiency, water conservation, water tariffs, and other approved activities or as directed by the CPUC, such as the Tax Act memorandum account. Balancing and memorandum accounts are recognized by San Jose Water Company when it is probable that future recovery of previously incurred costs or future refunds that are to be credited to customers will occur through the ratemaking process. In addition, in the case of special revenue programs such as the WCMA, San Jose Water Company follows the requirements of ASC Topic 980-605-25, “Alternative Revenue Programs” in determining revenue recognition, including the requirement that such revenues will be collected within 24 months of the year-end in which the revenue is recorded. A reserve is recorded for amounts SJW Group estimates will not be collected within the 24-month period. This reserve is based on an estimate of actual usage over the recovery period, offset by applicable drought surcharges, if any. In assessing the probability criteria for balancing and memorandum accounts between general rate cases, San Jose Water Company considers evidence that may exist prior to CPUC authorization that would satisfy ASC Topic 980 subtopic 340-25 recognition criteria. Such evidence may include regulatory rules and decisions, past practices, and other facts and circumstances that would indicate that recovery or refund is probable. When such evidence provides sufficient support, the balances are recorded in SJW Group’s financial statements. Based on ASC Topic 980-605-25, San Jose Water Company recognized regulatory assets of $4,118 and $3,410 due to lost revenues accumulated in the 2018 WCMA account for the three and six months ended June 30, 2018 , respectively. Of the $4,118 and $3,410 recognized in the 2018 WCMA account for the three and six months ended June 30, 2018 , respectively, a reserve of $407 was recorded which is the estimated amount that will not be collected within the 24-month period, as required by the guidance. The amounts have been reflected in the 2018 WCMA balance shown in the table below. Cost of capital memorandum account was approved by the CPUC on March 14, 2018. The account tracks the difference between current water rates and the lower rates adopted in the cost of capital decision on March 22, 2018. San Jose Water Company recorded a regulatory liability of $198 and $1,363 in the cost of capital memorandum account for the three and six months ended June 30, 2018 , respectively, with a corresponding reduction to revenue. The amount has been reflected in the cost of capital memorandum account balance shown in the table below. The CPUC directed San Jose Water Company to establish a memorandum account to capture the impact of the Tax Act on its regulated revenue requirement. The CPUC indicated that any benefit from implementing the new law should ultimately be passed on to ratepayers. Accordingly, San Jose Water Company recorded a regulatory liability of $4,563 and $5,496 in the tax memorandum account for the three and six months ended June 30, 2018 , respectively, with a corresponding reduction to revenue. The amount has been reflected in the tax memorandum account balance shown in the table below. San Jose Water Company re-evaluated the accounting for cost-recovery balancing and memorandum accounts under the new revenue recognition guidance, ASU 2014-09, “Revenue from Contracts with Customers.” Prior to adoption, San Jose Water Company recorded cost-recovery accounts as a component of revenue. Upon adoption of ASU 2014-09, San Jose Water Company began recording such balances as capitalized costs until recovery is approved by the CPUC. The change is reflected in the cost-recovery balancing and memorandum accounts as shown in the table below. Three months ended June 30, 2018 Three months ended June 30, 2017 Beginning Balance Regulatory Asset Increase (Decrease) Refunds (Collections) Surcharge Offset Ending Balance Beginning Balance Regulatory Asset Increase (Decrease) Refunds (Collections) Surcharge Offset Ending Balance Revenue accounts: 2014-2016 WCMA $ 270 93 2 — 365 $ 398 3,206 (556 ) (45 ) 3,003 2017 WCMA* 6,785 127 — — 6,912 — 4,989 — (3,988 ) 1,001 2018 WCMA* (708 ) 3,711 — — 3,003 — — — — — 2012 General Rate Case true-up 11,320 — 4 — 11,324 18,424 — (2,659 ) — 15,765 2015 General Rate Case true-up 115 — 2 — 117 4,097 — (1,686 ) — 2,411 Cost of capital memorandum account (1,309 ) (198 ) — — (1,507 ) (459 ) — 315 — (144 ) Tax memorandum account (933 ) (4,563 ) — — (5,496 ) — — — — — Drought surcharges — — — — — (5,054 ) — 60 4,033 (961 ) Cost-recovery accounts — — — — — 3,145 1,631 (369 ) — 4,407 All others 4,136 422 — — 4,558 3,516 426 (408 ) — 3,534 Total revenue accounts $ 19,676 (408 ) 8 — 19,276 $ 24,067 10,252 (5,303 ) — 29,016 Cost-recovery accounts: Water supply costs 8,197 1,190 — — 9,387 — — — — — Pension (2,298 ) 161 — — (2,137 ) — — — — — Total cost-recovery accounts $ 5,899 1,351 — — 7,250 $ — — — — — Total $ 25,575 943 8 — 26,526 $ 24,067 10,252 (5,303 ) — 29,016 Six months ended June 30, 2018 Six months ended June 30, 2017 Beginning Balance Regulatory Asset Increase (Decrease) Refunds (Collections) Surcharge Offset Ending Balance Beginning Balance Regulatory Asset Increase (Decrease) Refunds (Collections) Surcharge Offset Ending Balance Revenue accounts: 2014-2016 WCMA $ 190 173 2 — 365 $ 1,589 4,654 (1,788 ) (1,452 ) 3,003 2017 WCMA* 6,489 423 — — 6,912 — 7,049 — (6,048 ) 1,001 2018 WCMA* — 3,003 — — 3,003 — — — — — 2012 General Rate Case true-up 11,320 — 4 — 11,324 20,682 — (4,917 ) — 15,765 2015 General Rate Case true-up 115 — 2 — 117 5,528 — (3,117 ) — 2,411 Cost of capital memorandum account (144 ) (1,363 ) — — (1,507 ) (817 ) — 673 — (144 ) Tax memorandum account — (5,496 ) — — (5,496 ) — — — — — Drought surcharges — — — — — (7,688 ) — (773 ) 7,500 (961 ) Cost-recovery accounts — — — — — 3,181 2,001 (775 ) — 4,407 All others 3,736 822 — — 4,558 3,434 883 (859 ) 76 3,534 Total revenue accounts $ 21,706 (2,438 ) 8 — 19,276 $ 25,909 14,587 (11,556 ) 76 29,016 Cost-recovery accounts: Water supply costs 8,679 708 — — 9,387 — — — — — Pension (2,459 ) 322 — — (2,137 ) — — — — — Total cost-recovery accounts $ 6,220 1,030 — — 7,250 $ — — — — — Total $ 27,926 (1,408 ) 8 — 26,526 $ 25,909 14,587 (11,556 ) 76 29,016 * As of June 30, 2018 , the reserve balances for the 2017 and 2018 WCMA were $938 and $407 , respectively, which have been netted from the balances above. As of June 30, 2017 , the reserve balance for the 2017 WCMA was $276 which has been netted from the balance above. As of June 30, 2018 , the total balance in San Jose Water Company’s balancing and memorandum accounts combined, including interest, that has not been recorded into the financial statements was a net under-collection of $3,900 . All balancing accounts and memorandum-type accounts not included for recovery or refund in the current general rate case will be reviewed by the CPUC in San Jose Water Company’s next general rate case or at the time an individual account reaches a threshold of 2% of authorized revenue, whichever occurs first.

Regulatory Assets and Liabiliti

Regulatory Assets and Liabilities	6 Months Ended
	Jun. 30, 2018
Regulatory Assets and Liabilities Disclosure [Abstract]
Regulatory Assets and Liabilities	Regulatory Assets and Liabilities Regulatory assets and liabilities are comprised of the following as of June 30, 2018 and December 31, 2017 : June 30, 2018 December 31, 2017 Regulatory assets: Postretirement pensions and other medical benefits $ 68,556 68,556 Balancing and memorandum accounts, net 26,526 27,925 Other, net 3,250 3,073 Total regulatory assets, net in Consolidated Balance Sheets $ 98,332 99,554 Regulatory liability: Income tax temporary differences, net $ 61,639 62,476 Total regulatory liability in Consolidated Balance Sheets $ 61,639 62,476

California Water Service Group

California Water Service Group Stock California Water Service Group Stock	6 Months Ended
	Jun. 30, 2018
Investments, Debt and Equity Securities [Abstract]
California Water Service Group Stock	California Water Service Group Stock During the quarter ended March 31, 2018, SJW Group sold 17,660 shares of California Water Service Group for $716 , before fees of $2 . SJW Group recognized a loss on the sale of the stock of approximately $87 and tax benefit of approximately $24 , for a net loss of $63 . As of June 30, 2018 , SJW Group held 82,340 shares of California Water Service Group remaining. The company classifies its investment in California Water Service Group as available for sale. The stock is carried at the quoted market price with the changes in gain or loss reported as a component of other expense (income) on the Consolidated Statements of Comprehensive Income.

SJW Group and CTWS Merger Agree

SJW Group and CTWS Merger Agreement	6 Months Ended
	Jun. 30, 2018
Business Combinations [Abstract]
SJW GROUP AND CTWS MERGER AGREEMENT	SJW Group and CTWS Merger Agreement On March 14, 2018, SJW Group, Hydro Sub, Inc., a Connecticut corporation and a wholly-owned subsidiary of SJW Group and CTWS entered into an Agreement and Plan of Merger with regard to an all-stock transaction. On May 30, 2018, SJW Group, Hydro Sub, Inc. and CTWS entered into an Amended and Restated Agreement & Plan of Merger (the “Merger Agreement”), which provided, among other things, CTWS the right to solicit alternative proposals from third parties and take certain other actions relating to a “go-shop process” through July 14, 2018. Under the terms of the Merger Agreement, Hydro Sub, Inc. will merge with and into CTWS (the “Merger”), with CTWS surviving the Merger as a wholly-owned subsidiary of SJW Group. Subject to the terms and conditions of the Merger Agreement, at the time at which the Merger becomes effective (the “Effective Time”), each share of common stock, without par value, of CTWS (“CTWS Common Share”), other than CTWS Common Shares directly or indirectly owned by the company, Hydro Sub, Inc., CTWS or any of their respective subsidiaries (in each case, other than any CTWS Common Shares held on behalf of third parties), issued and outstanding immediately prior to the Effective Time will be converted into the right to receive 1.1375 shares of common stock of SJW Group, par value $0.001 . The transaction, which is expected to close during the fourth quarter of 2018, has been unanimously approved by the boards of directors of both companies. Consummation of the Merger is subject to customary conditions, including, without limitation: approval by SJW Group's stockholders and CTWS shareholders, approval by certain regulators, the approval by the New York Stock Exchange of the listing of common stock of SJW Group to be issued as consideration in the Merger; the absence of any law or judgment prohibiting the consummation of the Merger or the Charter Amendment; the effectiveness of the registration statement on Form S-4 relating to the shares of common stock to be issued in the Merger; the accuracy of the representations and warranties of the parties (subject to customary materiality qualifiers); each party’s performance in all material respects of its obligations contained in the Merger Agreement; the absence of any material adverse effect on the company or CTWS since the date of the Merger Agreement, which has not been ameliorated or cured; and the receipt by each party of customary opinions from counsel to the effect that the Merger will qualify as a reorganization for U.S. federal income tax purposes. There is no guarantee that all of the closing conditions and approvals will be satisfied, and the failure to complete the proposed merger may adversely affect the financial conditions and results of operations of SJW Group. In addition, SJW Group and CTWS have each received an unsolicited proposal. While each of the companies’ board of directors has determined that the respective proposals were neither superior proposals nor reasonably likely to lead to superior proposals, California Water Service Group filed on May 2, 2018 a preliminary proxy statement and on May 31, 2018 a definitive proxy statement to solicit proxies in opposition to the proposed merger, Eversource Energy filed on April 27, 2018 a preliminary proxy statement to solicit proxies in opposition to the proposed merger, and it is unclear what additional actions these third parties may take to further their proposals. In addition, on June 7, 2018, California Water Service Group filed a Schedule TO with the SEC and issued a press release announcing that it had commenced an unsolicited tender offer to acquire all outstanding shares of SJW Group for $68.25 per share in cash, following which, on June 15, 2018, SJW Group filed a Schedule 14D-9 with the SEC and issued a press release announcing the SJW Group board of director’s recommendation that stockholders reject the California Water Service Group tender offer and not tender their shares into the California Water Service Group tender offer and reaffirming SJW Group’s commitment to the proposed merger.

Legal Proceedings

Legal Proceedings	6 Months Ended
	Jun. 30, 2018
Commitments and Contingencies Disclosure [Abstract]
LEGAL PROCEEDINGS	Legal Proceedings 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, and Eric W. Thornburg, Chairman, President and Chief Executive Officer of SJW Group, CTWS and the Merger. The complaints allege that the CTWS board breached its fiduciary duties in connection with the Merger and that SJW Group and Mr. Thornburg aided and abetted such breaches. 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. At this time, SJW Group cannot determine the likelihood that liability exists on the part of SJW Group or Mr. Thornburg and we are unable to provide a reasonable estimate of potential loss, if any. 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.

Subsequent Event (Notes)

Subsequent Event (Notes)	6 Months Ended
	Jun. 30, 2018
Subsequent Event [Abstract]
Subsequent Events [Text Block]	Subsequent Event CLWSC completed its acquisition of the Deer Creek Ranch Water Co., LLC’s water system on July 2, 2018 for a purchase price of $2,700 . In 2017, CLWSC entered into an agreement to purchase the water system assets. Deer Creek Ranch includes approximately 750 service connections over an area of 1,191 acres in the Texas Hill Country on the rapidly growing western fringe of the Austin metropolitan area, about 40 miles south of CLWSC’s operating area of New Braunfels.

General (Policies)

General (Policies)	6 Months Ended
	Jun. 30, 2018
Organization, Consolidation and Presentation of Financial Statements [Abstract]
New Accounting Pronouncements and Changes in Accounting Principles [Text Block]	Recently Adopted Accounting Pronouncements In May 2014, the Financial Accounting Standards Board (“FASB”) issued Accounting Standard Update (“ASU”) 2014-09, “Revenue from Contracts with Customers.” The core principle of the guidance is that an entity should recognize revenue to depict the transfer of promised goods or services to customers in an amount that reflects the consideration to which the entity expects to be entitled in exchange for those goods or services. The new standard replaced most existing revenue recognition guidance in generally accepted accounting principles. The updated guidance also requires additional disclosures regarding the nature, timing and uncertainty of revenue transactions. SJW Group adopted the new revenue standard on January 1, 2018, using the modified retrospective method, and determined that no adjustment to the opening balance of retained earnings was necessary for contracts with remaining obligations as of the effective date. In addition, SJW Group applied the “right to invoice” practical expedient. The adoption of the new standard requires certain changes to the recognition of balancing and memorandum account revenue and related costs (See Note 9, “Balancing and Memorandum Accounts”). However, the changes did not have a material impact on our consolidated results of operations, financial position, or cash flows. Concurrently, the company implemented ASU 2017-10, “Identifying the Customer in a Service Concession Arrangement.” Upon adoption of ASU 2017-10, the service concession fee paid to the City of Cupertino was determined to be an up-front payment and accordingly will be amortized as a reduction to future revenue as opposed to amortized as an expense on SJW Group’s Consolidated Statements of Comprehensive Income. In January 2016, the FASB issued ASU 2016-01, “Financial Instruments - Overall” which changes the recognition of changes in fair value of financial liabilities when the fair value option is elected. In addition, the standard requires equity investments to be measured at fair value with changes in fair value recognized in net income instead of through other comprehensive income. The updated guidance affects the accounting for the company’s equity investment in California Water Service Group stock classified as an available-for-sale security (see Note 7 and Note 11 of “Notes to Unaudited Consolidated Financial Statements”). The new standard became effective for SJW Group beginning in the first quarter of the fiscal year ending December 31, 2018. Prior to adoption of ASU 2016-01, SJW Group recognized changes in fair value of its equity investment in California Water Service Group stock through other comprehensive income or loss on the statement of comprehensive income. Upon adoption on January 1, 2018, SJW Group began recording the change in fair value of its equity investment in other income and expense. In addition, the ASU stated that entities should apply the new standard by means of a cumulative-effect adjustment to the balance sheet as of the beginning of the fiscal year of adoption. As such, SJW Group recorded a cumulative-effect adjustment of $2,203 to beginning retained earnings to eliminate the cumulative change in fair value of its equity investment, net of tax from accumulated other comprehensive income. In October 2016, the FASB issued ASU 2016-16, “Intra-Entity Transfers of Assets Other Than Inventory,” which modifies existing guidance and is intended to reduce diversity in practice with respect to accounting for the income tax consequences of intra-entity transfers of assets. The ASU requires that the current and deferred income tax consequences of intra-entity transfers of assets be immediately recognized. Prior guidance allowed the entities to defer the consolidated tax consequences of an intercompany transfer of an asset other than inventory to a future period and amortize those tax consequences over time. SJW Group adopted ASU 2016-16 effective January 1, 2018. As SJW Group did not have any unamortized tax expense, the company did not have any cumulative catch-up adjustments upon adoption of this ASU. In March 2017, the FASB issued ASU 2017-07, “Improving the Presentation of Net Periodic Pension Cost and Net Periodic Postretirement Benefit Costs,” which requires employers to present the service cost component of the net periodic benefit cost in the same income statement line item as other employee compensation costs arising from services rendered during the period. The standard provides that only the service cost component of net periodic pension costs is eligible for asset capitalization. Companies should present the other components of net periodic benefit costs separately from the line items that include the service cost and outside of any subtotal of operating income, if one is presented. ASU 2017-07 requires retrospective presentation in the income statement of the service cost component and the other components of net periodic cost and net periodic postretirement benefit cost and prospective presentation from date of adoption for the capitalization in assets of only the service cost component of net periodic cost and net periodic postretirement benefit cost. SJW Group adopted ASU 2017-07 effective January 1, 2018. As such, the consolidated statements of comprehensive income for the periods presented have been reclassified to reflect the retrospective changes. See Note 4 of “Defined Benefit Plan” for further discussion.
Revenue Recognition, Policy [Policy Text Block]
Basis of Accounting, Policy	The unaudited interim financial information has been prepared in accordance with accounting principles generally accepted in the United States of America (“GAAP”) and in accordance with the instructions for Form 10-Q and Rule 10-01 of Regulation S-X promulgated by the Securities and Exchange Commission (the “SEC”). The Notes to Consolidated Financial Statements in SJW Group’s 2017 Annual Report on Form 10-K should be read with the accompanying unaudited condensed consolidated financial statements.
Earnings Per Share, Policy	Basic earnings per share is calculated using income available to common stockholders, divided by the weighted average number of shares outstanding during the period. Diluted earnings per share is calculated using income available to common stockholders divided by the weighted average number of shares of common stock including both shares outstanding and shares potentially issuable in connection with deferred restricted common stock awards under SJW Group’s Long-Term Incentive Plan (as amended, the “Incentive Plan”) and shares potentially issuable under the Employee Stock Purchase Plan (“ESPP”).

General Revenue (Tables)

General Revenue (Tables)	6 Months Ended
	Jun. 30, 2018
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Major Streams of Revenue	The major streams of revenue for SJW Group are as follows: Three months ended June 30, Six months ended June 30, 2018 2017 2018 2017 Revenue from contracts with customers $ 98,443 95,857 $ 174,312 164,424 Alternative revenue programs, net - WCMA 3,933 7,639 3,601 9,915 Other balancing and memorandum accounts revenue, net * (4,611 ) (2,750 ) (6,447 ) (6,111 ) Rental income 1,321 1,327 2,662 2,890 $ 99,086 102,073 $ 174,128 171,118 * The amount reflected for three and six months ended June 30, 2018 , excludes a further addition of $1,351 and $1,030 , respectively, to revenue related to cost-recovery balancing accounts which upon adoption of Topic 606 are recorded as capitalized costs until recovery is approved by the CPUC. During 2017, prior to adoption of Topic 606, these amounts were recorded as revenue. For further discussion, please see Note 9.

Equity Plans (Tables)

Equity Plans (Tables)	6 Months Ended
	Jun. 30, 2018
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Schedule of Compensation Cost for Share-based Payment Arrangements, Allocation of Share-based Compensation Costs by Plan	A summary of compensation costs charged to income, proceeds from the exercise of stock options and similar instruments, and the tax benefit realized from stock options and similar instruments exercised, that were recorded to additional paid-in capital and common stock, by award type, are presented below for the three and six months ended June 30, 2018 , and 2017 . Three months ended June 30, Six months ended June 30, 2018 2017 2018 2017 Adjustments to additional paid-in capital and common stock for: Compensation costs charged to income: ESPP $ — — $ 115 100 Restricted stock and deferred restricted stock 392 458 764 944 Total compensation costs charged to income $ 392 458 $ 879 1,044 Proceeds from ESPP $ — — $ 653 570

Real Estate Investments (Tables

Real Estate Investments (Tables)	6 Months Ended
	Jun. 30, 2018
Real Estate Investments, Net [Abstract]
Schedule of Real Estate Investments	The major components of real estate investments as of June 30, 2018 , and December 31, 2017 , are as follows: June 30, December 31, Land $ 13,262 13,262 Buildings and improvements 43,074 42,951 Subtotal 56,336 56,213 Less: accumulated depreciation and amortization 11,730 11,132 Total $ 44,606 45,081

Defined Benefit Plan (Tables)

Defined Benefit Plan (Tables)	6 Months Ended
	Jun. 30, 2018
Retirement Benefits [Abstract]
Schedule of Net Benefit Costs	June 30, 2017 , utility plant included $265 of pension non-service cost in utility plant. The components of net periodic benefit cost have been recorded in the consolidated statements of comprehensive income as follows: Three months ended June 30, Six months ended June 30, 2018 2017 2018 2017 Other production expenses $ 426 336 $ 849 685 Administrative and general expense 902 723 1,797 1,464 Maintenance expense 279 229 557 465 Pension non-service costs 595 1,032 1,178 1,907 $ 2,202 2,320 $ 4,381 4,521 The components of net periodic benefit costs for San Jose Water Company’s pension plan, its Executive Supplemental Retirement Plan, Cash Balance Executive Supplemental Retirement Plan and Social Welfare Plan for the three and six months ended June 30, 2018 , and 2017 are as follows: Three months ended June 30, Six months ended June 30, 2018 2017 2018 2017 Service cost $ 1,607 1,288 $ 3,203 2,614 Interest cost 1,876 1,920 3,753 3,823 Other cost 1,145 1,165 2,278 2,203 Expected return on assets (2,426 ) (2,053 ) (4,853 ) (4,119 ) $ 2,202 2,320 $ 4,381 4,521
Schedule of Allocation of Plan Assets	The following tables summarize the fair values of plan assets by major categories as of June 30, 2018 , and December 31, 2017 : Fair Value Measurements at June 30, 2018 Quoted Prices in Active Markets for Identical Assets Significant Observable Inputs Significant Unobservable Inputs Asset Category Benchmark Total (Level 1) (Level 2) (Level 3) Cash and cash equivalents — $ 5,309 $ 5,309 $ — $ — Actively Managed (a): All Cap Equity Russell 3000 Value 6,450 6,408 42 — U.S. Large Cap Equity Russell 1000, Russell 1000 Growth, Russell 1000 Value 52,125 52,125 — — U.S. Mid Cap Equity Russell Mid Cap, Russell Mid Cap Growth, Russell Mid Cap Value 9,628 9,628 — — U.S. Small Cap Equity Russell 2000, Russell 2000 Growth, Russell 2000 Value 9,805 9,805 — — Non-U.S. Large Cap Equity MSCI EAFE 5,759 5,759 — — REIT NAREIT - Equity REIT’S 6,276 — 6,276 — Fixed Income (b) (b) 45,153 — 45,153 — Total $ 140,505 $ 89,034 $ 51,471 $ — The Plan has a current target allocation of 55% invested in a diversified array of equity securities to provide long-term capital appreciation and 45% invested in a diversified array of fixed income securities and cash to provide preservation of capital plus generation of income. (a) Actively managed portfolio of securities with the goal to exceed the stated benchmark performance. (b) Actively managed portfolio of fixed income securities with the goal to exceed the Barclays 1-5 Year Government/Credit, Barclays Intermediate Government/Credit, and Merrill Lynch Preferred Stock Fixed Rate. Fair Value Measurements at December 31, 2017 Quoted Prices in Active Markets for Identical Assets Significant Observable Inputs Significant Unobservable Inputs Asset Category Benchmark Total (Level 1) (Level 2) (Level 3) Cash and cash equivalents — $ 8,207 $ 8,207 $ — $ — Actively Managed (a): All Cap Equity Russell 3000 Value 6,413 6,376 37 — U.S. Large Cap Equity Russell 1000, Russell 1000 Growth, Russell 1000 Value 50,351 50,351 — — U.S. Mid Cap Equity Russell Mid Cap, Russell Mid Cap Growth, Russell Mid Cap Value 9,358 9,358 — — U.S. Small Cap Equity Russell 2000, Russell 2000 Growth, Russell 2000 Value 8,725 8,725 — — Non-U.S. Large Cap Equity MSCI EAFE 5,973 5,973 — — REIT NAREIT - Equity REIT’S 6,143 — 6,143 — Fixed Income (b) (b) 44,994 — 44,994 — Total $ 140,164 $ 88,990 $ 51,174 $ — The Plan has a current target allocation of 55% invested in a diversified array of equity securities to provide long-term capital appreciation and 45% invested in a diversified array of fixed income securities and cash to provide preservation of capital plus generation of income. (a) Actively managed portfolio of securities with the goal to exceed the stated benchmark performance. (b) Actively managed portfolio of fixed income securities with the goal to exceed the Barclays 1-5 Year Government/Credit, Barclays Intermediate Government/Credit, and Merrill Lynch Preferred Stock Fixed Rate.

Segment and Non-Tariffed Busi25

Segment and Non-Tariffed Business Reporting (Tables)	6 Months Ended
	Jun. 30, 2018
Segment Reporting [Abstract]
Schedule of Segment Reporting Information, by Segment	The following tables set forth information relating to SJW Group’s reportable segments and distribution of regulated and non-tariffed business activities within the reportable segments. Certain allocated assets, revenue and expenses have been included in the reportable segment amounts. Other business activity of SJW Group not included in the reportable segments is included in the “All Other” category. For Three Months Ended June 30, 2018 Water Utility Services Real Estate Services All Other* SJW Group Regulated Non-tariffed Non-tariffed Non-tariffed Regulated Non-tariffed Total Operating revenue $ 95,798 1,967 1,321 — 95,798 3,288 99,086 Operating expense 70,642 1,278 891 3,476 70,642 5,645 76,287 Operating income (loss) 25,156 689 430 (3,476 ) 25,156 (2,357 ) 22,799 Net income (loss) before noncontrolling interest 15,022 497 296 (2,944 ) 15,022 (2,151 ) 12,871 Depreciation and amortization 13,272 85 299 — 13,272 384 13,656 Senior note and other interest expense 5,540 — — 544 5,540 544 6,084 Income tax expense (benefit) in net income 4,650 193 92 (867 ) 4,650 (582 ) 4,068 Assets $ 1,449,714 3,768 46,756 (117 ) 1,449,714 50,407 1,500,121 For Three Months Ended June 30, 2017 Water Utility Services Real Estate Services All Other* SJW Group Regulated Non-tariffed Non-tariffed Non-tariffed Regulated Non-tariffed Total Operating revenue $ 98,836 1,910 1,327 — 98,836 3,237 102,073 Operating expense 67,285 1,223 942 804 67,285 2,969 70,254 Operating income (loss) 31,551 687 385 (804 ) 31,551 268 31,819 Net income (loss) before noncontrolling interest 16,080 320 5,321 (1,137 ) 16,080 4,504 20,584 Depreciation and amortization 11,592 142 299 — 11,592 441 12,033 Senior note, mortgage and other interest expense 5,215 — (3 ) 544 5,215 541 5,756 Income tax expense (benefit) in net income 9,908 236 1,988 (168 ) 9,908 2,056 11,964 Assets $ 1,398,567 19,358 49,337 3,924 1,398,567 72,619 1,471,186 For Six Months Ended June 30, 2018 Water Utility Services Real Estate Services All Other* SJW Group Regulated Non-tariffed Non-tariffed Non-tariffed Regulated Non-tariffed Total Operating revenue $ 168,151 3,315 2,662 — 168,151 5,977 174,128 Operating expense 132,343 2,166 1,740 7,749 132,343 11,655 143,998 Operating income (loss) 35,808 1,149 922 (7,749 ) 35,808 (5,678 ) 30,130 Net income (loss) 19,817 828 652 (7,141 ) 19,817 (5,661 ) 14,156 Depreciation and amortization 26,473 168 598 — 26,473 766 27,239 Senior note and other interest expense 11,048 — — 1,088 11,048 1,088 12,136 Income tax expense (benefit) in net income 5,142 322 186 (2,162 ) 5,142 (1,654 ) 3,488 Assets $ 1,449,714 3,768 46,756 (117 ) 1,449,714 50,407 1,500,121 For Six Months Ended June 30, 2017 Water Utility Services Real Estate Services All Other* SJW Group Regulated Non-tariffed Non-tariffed Non-tariffed Regulated Non-tariffed Total Operating revenue $ 165,054 3,174 2,890 — 165,054 6,064 171,118 Operating expense 122,031 2,054 1,890 1,616 122,031 5,560 127,591 Operating income (loss) 43,023 1,120 1,000 (1,616 ) 43,023 504 43,527 Net income (loss) 20,029 492 5,681 (1,947 ) 20,029 4,226 24,255 Depreciation and amortization 23,252 278 622 — 23,252 900 24,152 Senior note, mortgage and other interest expense 10,640 — 62 1,111 10,640 1,173 11,813 Income tax expense (benefit) in net income 11,701 373 2,116 (658 ) 11,701 1,831 13,532 Assets $ 1,398,567 19,358 49,337 3,924 1,398,567 72,619 1,471,186 * The “All Other” category includes the accounts of SJW Group and Hydro Sub, Inc. on a stand-alone basis. For the six months ended June 30, 2018 , Hydro Sub, Inc. had no recorded revenue or expenses and as of June 30, 2018 , held no assets and had incurred no liabilities. For the six months ended June 30, 2017 , the “All Other” category includes the accounts of SJW Group on a stand-alone basis.

Balancing and Memorandum Acco26

Balancing and Memorandum Account Recovery Procedures (Tables)	6 Months Ended
	Jun. 30, 2018
Regulated Operations [Abstract]
Public Utilities General Disclosures	Three months ended June 30, 2018 Three months ended June 30, 2017 Beginning Balance Regulatory Asset Increase (Decrease) Refunds (Collections) Surcharge Offset Ending Balance Beginning Balance Regulatory Asset Increase (Decrease) Refunds (Collections) Surcharge Offset Ending Balance Revenue accounts: 2014-2016 WCMA $ 270 93 2 — 365 $ 398 3,206 (556 ) (45 ) 3,003 2017 WCMA* 6,785 127 — — 6,912 — 4,989 — (3,988 ) 1,001 2018 WCMA* (708 ) 3,711 — — 3,003 — — — — — 2012 General Rate Case true-up 11,320 — 4 — 11,324 18,424 — (2,659 ) — 15,765 2015 General Rate Case true-up 115 — 2 — 117 4,097 — (1,686 ) — 2,411 Cost of capital memorandum account (1,309 ) (198 ) — — (1,507 ) (459 ) — 315 — (144 ) Tax memorandum account (933 ) (4,563 ) — — (5,496 ) — — — — — Drought surcharges — — — — — (5,054 ) — 60 4,033 (961 ) Cost-recovery accounts — — — — — 3,145 1,631 (369 ) — 4,407 All others 4,136 422 — — 4,558 3,516 426 (408 ) — 3,534 Total revenue accounts $ 19,676 (408 ) 8 — 19,276 $ 24,067 10,252 (5,303 ) — 29,016 Cost-recovery accounts: Water supply costs 8,197 1,190 — — 9,387 — — — — — Pension (2,298 ) 161 — — (2,137 ) — — — — — Total cost-recovery accounts $ 5,899 1,351 — — 7,250 $ — — — — — Total $ 25,575 943 8 — 26,526 $ 24,067 10,252 (5,303 ) — 29,016 Six months ended June 30, 2018 Six months ended June 30, 2017 Beginning Balance Regulatory Asset Increase (Decrease) Refunds (Collections) Surcharge Offset Ending Balance Beginning Balance Regulatory Asset Increase (Decrease) Refunds (Collections) Surcharge Offset Ending Balance Revenue accounts: 2014-2016 WCMA $ 190 173 2 — 365 $ 1,589 4,654 (1,788 ) (1,452 ) 3,003 2017 WCMA* 6,489 423 — — 6,912 — 7,049 — (6,048 ) 1,001 2018 WCMA* — 3,003 — — 3,003 — — — — — 2012 General Rate Case true-up 11,320 — 4 — 11,324 20,682 — (4,917 ) — 15,765 2015 General Rate Case true-up 115 — 2 — 117 5,528 — (3,117 ) — 2,411 Cost of capital memorandum account (144 ) (1,363 ) — — (1,507 ) (817 ) — 673 — (144 ) Tax memorandum account — (5,496 ) — — (5,496 ) — — — — — Drought surcharges — — — — — (7,688 ) — (773 ) 7,500 (961 ) Cost-recovery accounts — — — — — 3,181 2,001 (775 ) — 4,407 All others 3,736 822 — — 4,558 3,434 883 (859 ) 76 3,534 Total revenue accounts $ 21,706 (2,438 ) 8 — 19,276 $ 25,909 14,587 (11,556 ) 76 29,016 Cost-recovery accounts: Water supply costs 8,679 708 — — 9,387 — — — — — Pension (2,459 ) 322 — — (2,137 ) — — — — — Total cost-recovery accounts $ 6,220 1,030 — — 7,250 $ — — — — — Total $ 27,926 (1,408 ) 8 — 26,526 $ 25,909 14,587 (11,556 ) 76 29,016 * As of June 30, 2018 , the reserve balances for the 2017 and 2018 WCMA were $938 and $407 , respectively, which have been netted from the balances above. As of June 30, 2017 , the reserve balance for the 2017 WCMA was $276 which has been netted from the balance above.

Regulatory Assets and Liabili27

Regulatory Assets and Liabilities (Tables)	6 Months Ended
	Jun. 30, 2018
Regulatory Assets and Liabilities Disclosure [Abstract]
Schedule of Regulatory Assets	Regulatory assets and liabilities are comprised of the following as of June 30, 2018 and December 31, 2017 : June 30, 2018 December 31, 2017 Regulatory assets: Postretirement pensions and other medical benefits $ 68,556 68,556 Balancing and memorandum accounts, net 26,526 27,925 Other, net 3,250 3,073 Total regulatory assets, net in Consolidated Balance Sheets $ 98,332 99,554 Regulatory liability: Income tax temporary differences, net $ 61,639 62,476 Total regulatory liability in Consolidated Balance Sheets $ 61,639 62,476

General - Additional Informatio

General - Additional Information (Details) - USD ($) $ in Thousands	Jun. 14, 2016	Jun. 30, 2017
Regulatory Assets [Line Items]
Water reduction target goal (percent)	20.00%
Accounting Standards Update 2016-09, Statutory Tax Withholding Component
Regulatory Assets [Line Items]
Excess tax benefit		$ 2,203

General - Schedule of Major Str

General - Schedule of Major Streams of Revenue (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Revenue from contracts with customers	$ 98,443	$ 95,857	$ 174,312	$ 164,424
Alternative revenue programs, net - WCMA	3,933	7,639	3,601	9,915
Other balancing and memorandum accounts revenue, net	(4,611)	(2,750)	(6,447)	(6,111)
Rental income	1,321	1,327	2,662	2,890
Total revenues	99,086	$ 102,073	174,128	$ 171,118
Reduction of revenue related to cost-recovery balancing accounts	$ 1,351		$ 1,030

General - Earnings Per Share (D

General - Earnings Per Share (Details) - shares	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Restricted Stock and Stock Options
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Anti-dilutive restricted common stock units excluded from computation of earnings per share (shares)	2,094	981	3,256	2,987

General - Depreciation (Details

General - Depreciation (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
General and Administrative Expense
Public Utility, Property, Plant and Equipment [Line Items]
Depreciation	$ 572	$ 579	$ 1,150	$ 1,106

Equity Plans (Details)

Equity Plans (Details) $ / shares in Units, $ in Thousands	Apr. 25, 2018$ / shares	Jan. 30, 2018$ / sharesshares	Jan. 02, 2018vesting_installment$ / sharesshares	Jun. 30, 2018USD ($)shares	Jun. 30, 2017USD ($)	Jun. 30, 2018USD ($)shares	Jun. 30, 2017USD ($)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation costs charged to income: | $				$ 392	$ 458	$ 879	$ 1,044
Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Grant date fair value of equity instruments granted (usd per share) | $ / shares			$ 60.22
Restricted stock and deferred restricted stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation costs charged to income: | $				392	458	$ 764	944
Recognition period for unrecognized compensation cost						1 year 7 months 2 days
Unrecognized compensation costs | $				$ 2,462		$ 2,462
Key officers | Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of equity instruments granted (shares) | shares			12,296
Number of equal successive installments for vesting of stock awards (vesting installments) | vesting_installment			3
Key officers | Performance Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of equity instruments granted (shares) | shares		4,081
Key officers | Performance Shares | Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Target vesting percentage		0.00%
Key officers | Performance Shares | Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Grant date fair value of equity instruments granted (usd per share) | $ / shares		$ 58.02
Target vesting percentage		150.00%
Key officers | Performance Shares 2
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of equity instruments granted (shares) | shares		5,259
Grant date fair value of equity instruments granted (usd per share) | $ / shares		$ 55.89
Key officers | Performance Shares 2 | Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Target vesting percentage		0.00%
Key officers | Performance Shares 2 | Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Target vesting percentage		150.00%
Key officers | Performance Shares 3
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of equity instruments granted (shares) | shares		6,342
Grant date fair value of equity instruments granted (usd per share) | $ / shares		$ 63.85
Key officers | Performance Shares 3 | Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Target vesting percentage		0.00%
Key officers | Performance Shares 3 | Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Target vesting percentage		200.00%
Director [Member] | Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Grant date fair value of equity instruments granted (usd per share) | $ / shares	$ 55.8
Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Remaining shares available for issuance under the Incentive Plan (shares) | shares				881,914		881,914
Shares issuable upon exercise of Incentive Plan awards (shares) | shares						190,405
Employee Stock Purchase Plan (ESPP)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation costs charged to income: | $				$ 0	0	$ 115	100
Proceeds from ESPP | $				$ 0	0	$ 653	570
Purchase price of common stock under ESPP (percent)						85.00%
Maximum percentage of base compensation employees can designate for stock purchases under ESPP (percent)				10.00%		10.00%
Plan expense | $				$ 62	$ 54	$ 132	$ 117
Unrecognized compensation costs | $				$ 23		$ 23
Employee Stock Purchase Plan (ESPP) | Common Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorized for issuance under the plan (shares) | shares				400,000		400,000

Real Estate Investments (Detail

Real Estate Investments (Details) - USD ($) $ in Thousands	Apr. 06, 2017	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017	Dec. 31, 2017
Schedule of Investments [Line Items]
Land		$ 13,262		$ 13,262		$ 13,262
Buildings and improvements		43,074		43,074		42,951
Subtotal		56,336		56,336		56,213
Less accumulated depreciation and amortization		11,730		11,730		11,132
Total		44,606		44,606		$ 45,081
Gain on sale of real estate investments		$ 0	$ 6,903	$ 0	$ 6,903
Minimum
Schedule of Investments [Line Items]
Estimated useful life				7 years
Maximum
Schedule of Investments [Line Items]
Estimated useful life				39 years
Partnership Interest [Member]
Schedule of Investments [Line Items]
Limited Liability Company or Limited Partnership, Members or Limited Partners, Ownership Interest				70.00%
444 West Santa Clara Street [Member] | Partnership Interest [Member]
Schedule of Investments [Line Items]
Proceeds from Sale of Real Estate Held-for-investment	$ 11,000
Gain on sale of real estate investments	6,323
Real Estate Selling Expenses	1,157
444 West Santa Clara Street [Member] | Parent [Member]
Schedule of Investments [Line Items]
Gain on sale of real estate investments	4,427
444 West Santa Clara Street [Member] | Noncontrolling Interest [Member]
Schedule of Investments [Line Items]
Gain on sale of real estate investments	1,896
CA Undeveloped Land [Member]
Schedule of Investments [Line Items]
Proceeds from Sale of Real Estate Held-for-investment	1,350
Gain on sale of real estate investments	580
Real Estate Selling Expenses	$ 14

Defined Benefit Plan (Details)

Defined Benefit Plan (Details) - USD ($) $ in Thousands	3 Months Ended			6 Months Ended
	Jun. 30, 2018		Jun. 30, 2017	Jun. 30, 2018		Jun. 30, 2017	Dec. 31, 2017
Net Periodic Benefit Cost - Comprehensive Income Presentation [Abstract]
Pension non-service cost	$ 595		$ 1,032	$ 1,178		$ 1,907
Components of Net Periodic Benefit Cost [Abstract]
Service cost	1,607		1,288	3,203		2,614
Interest cost	1,876		1,920	3,753		3,823
Other cost	1,145		1,165	2,278		2,203
Expected return on assets	(2,426)		(2,053)	(4,853)		(4,119)
Net periodic benefit cost	2,202		2,320	4,381		4,521
Plan Assets [Abstract]
Fair value of plan assets	140,505			140,505			$ 140,164
Employer Contributions [Abstract]
Capitalized pension non-service cost			265			265
Estimated employer contributions for the current fiscal year	7,450			7,450
Defined Contribution Plan, Employer Discretionary Contribution Amount				1,420
Quoted Prices in Active Markets for Identical Assets
Plan Assets [Abstract]
Fair value of plan assets	89,034			89,034			88,990
Significant Observable Inputs
Plan Assets [Abstract]
Fair value of plan assets	51,471			51,471			51,174
Significant Unobservable Inputs
Plan Assets [Abstract]
Fair value of plan assets	$ 0			$ 0			0
Equity Securities [Member]
Plan Assets [Abstract]
Target plan asset allocations	55.00%			55.00%
Fixed Income Securities
Plan Assets [Abstract]
Target plan asset allocations	45.00%			45.00%
Cash and cash equivalents
Plan Assets [Abstract]
Fair value of plan assets	$ 5,309			$ 5,309			8,207
Cash and cash equivalents | Quoted Prices in Active Markets for Identical Assets
Plan Assets [Abstract]
Fair value of plan assets	5,309			5,309			8,207
Cash and cash equivalents | Significant Observable Inputs
Plan Assets [Abstract]
Fair value of plan assets	0			0			0
Cash and cash equivalents | Significant Unobservable Inputs
Plan Assets [Abstract]
Fair value of plan assets	0			0			0
Actively Managed | All Cap Equity
Plan Assets [Abstract]
Fair value of plan assets	6,450	[1]		6,450	[1]		6,413	[2]
Actively Managed | All Cap Equity | Quoted Prices in Active Markets for Identical Assets
Plan Assets [Abstract]
Fair value of plan assets	6,408	[1]		6,408	[1]		6,376	[2]
Actively Managed | All Cap Equity | Significant Observable Inputs
Plan Assets [Abstract]
Fair value of plan assets	42	[1]		42	[1]		37	[2]
Actively Managed | All Cap Equity | Significant Unobservable Inputs
Plan Assets [Abstract]
Fair value of plan assets	0	[1]		0	[1]		0	[2]
Actively Managed | U.S. Large Cap Equity
Plan Assets [Abstract]
Fair value of plan assets	52,125	[1]		52,125	[1]		50,351	[2]
Actively Managed | U.S. Large Cap Equity | Quoted Prices in Active Markets for Identical Assets
Plan Assets [Abstract]
Fair value of plan assets	52,125	[1]		52,125	[1]		50,351	[2]
Actively Managed | U.S. Large Cap Equity | Significant Observable Inputs
Plan Assets [Abstract]
Fair value of plan assets	0	[1]		0	[1]		0	[2]
Actively Managed | U.S. Large Cap Equity | Significant Unobservable Inputs
Plan Assets [Abstract]
Fair value of plan assets	0	[1]		0	[1]		0	[2]
Actively Managed | U.S. Mid Cap Equity
Plan Assets [Abstract]
Fair value of plan assets	9,628	[1]		9,628	[1]		9,358	[2]
Actively Managed | U.S. Mid Cap Equity | Quoted Prices in Active Markets for Identical Assets
Plan Assets [Abstract]
Fair value of plan assets	9,628	[1]		9,628	[1]		9,358	[2]
Actively Managed | U.S. Mid Cap Equity | Significant Observable Inputs
Plan Assets [Abstract]
Fair value of plan assets	0	[1]		0	[1]		0	[2]
Actively Managed | U.S. Mid Cap Equity | Significant Unobservable Inputs
Plan Assets [Abstract]
Fair value of plan assets	0	[1]		0	[1]		0	[2]
Actively Managed | U.S. Small Cap Equity
Plan Assets [Abstract]
Fair value of plan assets	9,805	[1]		9,805	[1]		8,725	[2]
Actively Managed | U.S. Small Cap Equity | Quoted Prices in Active Markets for Identical Assets
Plan Assets [Abstract]
Fair value of plan assets	9,805	[1]		9,805	[1]		8,725	[2]
Actively Managed | U.S. Small Cap Equity | Significant Observable Inputs
Plan Assets [Abstract]
Fair value of plan assets	0	[1]		0	[1]		0	[2]
Actively Managed | U.S. Small Cap Equity | Significant Unobservable Inputs
Plan Assets [Abstract]
Fair value of plan assets	0	[1]		0	[1]		0	[2]
Actively Managed | Non-U.S. Large Cap Equity
Plan Assets [Abstract]
Fair value of plan assets	5,759	[1]		5,759	[1]		5,973	[2]
Actively Managed | Non-U.S. Large Cap Equity | Quoted Prices in Active Markets for Identical Assets
Plan Assets [Abstract]
Fair value of plan assets	5,759	[1]		5,759	[1]		5,973	[2]
Actively Managed | Non-U.S. Large Cap Equity | Significant Observable Inputs
Plan Assets [Abstract]
Fair value of plan assets	0	[1]		0	[1]		0	[2]
Actively Managed | Non-U.S. Large Cap Equity | Significant Unobservable Inputs
Plan Assets [Abstract]
Fair value of plan assets	0	[1]		0	[1]		0	[2]
Actively Managed | REIT
Plan Assets [Abstract]
Fair value of plan assets	6,276	[1]		6,276	[1]		6,143	[2]
Actively Managed | REIT | Quoted Prices in Active Markets for Identical Assets
Plan Assets [Abstract]
Fair value of plan assets	0	[1]		0	[1]		0	[2]
Actively Managed | REIT | Significant Observable Inputs
Plan Assets [Abstract]
Fair value of plan assets	6,276	[1]		6,276	[1]		6,143	[2]
Actively Managed | REIT | Significant Unobservable Inputs
Plan Assets [Abstract]
Fair value of plan assets	0	[1]		0	[1]		0	[2]
Fixed Income
Plan Assets [Abstract]
Fair value of plan assets	45,153	[3]		45,153	[3]		44,994	[4]
Fixed Income | Quoted Prices in Active Markets for Identical Assets
Plan Assets [Abstract]
Fair value of plan assets	0	[3]		0	[3]		0	[4]
Fixed Income | Significant Observable Inputs
Plan Assets [Abstract]
Fair value of plan assets	45,153	[3]		45,153	[3]		44,994	[4]
Fixed Income | Significant Unobservable Inputs
Plan Assets [Abstract]
Fair value of plan assets	0	[3]		0	[3]		$ 0	[4]
ASU 2017-07
Net Periodic Benefit Cost - Comprehensive Income Presentation [Abstract]
Administrative and general	902		723	1,797		1,464
Maintenance expense	279		229	557		465
Pension non-service cost	595		1,032	1,178		1,907
Components of Net Periodic Benefit Cost [Abstract]
Other cost	426		336	849		685
Net periodic benefit cost	$ 2,202		$ 2,320	$ 4,381		$ 4,521
[1]	Actively managed portfolio of securities with the goal to exceed the stated benchmark performance.
[2]	Actively managed portfolio of securities with the goal to exceed the stated benchmark performance.
[3]	Actively managed portfolio of fixed income securities with the goal to exceed the Barclays 1-5 Year Government/Credit, Barclays Intermediate Government/Credit, and Merrill Lynch Preferred Stock Fixed Rate.
[4]	Actively managed portfolio of fixed income securities with the goal to exceed the Barclays 1-5 Year Government/Credit, Barclays Intermediate Government/Credit, and Merrill Lynch Preferred Stock Fixed Rate.

Segment and Non-Tariffed Busi35

Segment and Non-Tariffed Business Reporting (Details) $ in Thousands		3 Months Ended		6 Months Ended
		Jun. 30, 2018USD ($)	Jun. 30, 2017USD ($)	Jun. 30, 2018USD ($)subsidiaryreportable_segment	Jun. 30, 2017USD ($)	Dec. 31, 2017USD ($)
Segment Reporting Information [Line Items]
Number of subsidiaries | subsidiary				4
Number of reportable business segments | reportable_segment				2
Operating revenue		$ 99,086	$ 102,073	$ 174,128	$ 171,118
Operating expense		76,287	70,254	143,998	127,591
Operating income (loss)		22,799	31,819	30,130	43,527
Net income (loss) before noncontrolling interest		12,871	20,584	14,156	24,255
Depreciation and amortization		13,656	12,033	27,239	24,152
Senior note and other interest expense		6,084	5,756	12,136	11,813
Income tax expense (benefit) in net income		4,068	11,964	3,488	13,532
Assets		1,500,121	1,471,186	1,500,121	1,471,186	$ 1,458,001
Water Utility Services | Regulated
Segment Reporting Information [Line Items]
Operating revenue		95,798	98,836	168,151	165,054
Operating expense		70,642	67,285	132,343	122,031
Operating income (loss)		25,156	31,551	35,808	43,023
Net income (loss) before noncontrolling interest		15,022	16,080	19,817	20,029
Depreciation and amortization		13,272	11,592	26,473	23,252
Senior note and other interest expense		5,540	5,215	11,048	10,640
Income tax expense (benefit) in net income		4,650	9,908	5,142	11,701
Assets		1,449,714	1,398,567	1,449,714	1,398,567
Water Utility Services | Non-tariffed
Segment Reporting Information [Line Items]
Operating revenue		1,967	1,910	3,315	3,174
Operating expense		1,278	1,223	2,166	2,054
Operating income (loss)		689	687	1,149	1,120
Net income (loss) before noncontrolling interest		497	320	828	492
Depreciation and amortization		85	142	168	278
Senior note and other interest expense		0	0	0	0
Income tax expense (benefit) in net income		193	236	322	373
Assets		3,768	19,358	3,768	19,358
Real Estate Services | Non-tariffed
Segment Reporting Information [Line Items]
Operating revenue		1,321	1,327	2,662	2,890
Operating expense		891	942	1,740	1,890
Operating income (loss)		430	385	922	1,000
Net income (loss) before noncontrolling interest		296	5,321	652	5,681
Depreciation and amortization		299	299	598	622
Senior note and other interest expense		0	(3)	0	62
Income tax expense (benefit) in net income		92	1,988	186	2,116
Assets		46,756	49,337	46,756	49,337
All Other | Non-tariffed
Segment Reporting Information [Line Items]
Operating revenue	[1]	0	0	0	0
Operating expense	[1]	3,476	804	7,749	1,616
Operating income (loss)	[1]	(3,476)	(804)	(7,749)	(1,616)
Net income (loss) before noncontrolling interest	[1]	(2,944)	(1,137)	(7,141)	(1,947)
Depreciation and amortization	[1]	0	0	0	0
Senior note and other interest expense	[1]	544	544	1,088	1,111
Income tax expense (benefit) in net income	[1]	(867)	(168)	(2,162)	(658)
Assets	[1]	(117)	3,924	(117)	3,924
SJW Group | Regulated
Segment Reporting Information [Line Items]
Operating revenue		95,798	98,836	168,151	165,054
Operating expense		70,642	67,285	132,343	122,031
Operating income (loss)		25,156	31,551	35,808	43,023
Net income (loss) before noncontrolling interest		15,022	16,080	19,817	20,029
Depreciation and amortization		13,272	11,592	26,473	23,252
Senior note and other interest expense		5,540	5,215	11,048	10,640
Income tax expense (benefit) in net income		4,650	9,908	5,142	11,701
Assets		1,449,714	1,398,567	1,449,714	1,398,567
SJW Group | Non-tariffed
Segment Reporting Information [Line Items]
Operating revenue		3,288	3,237	5,977	6,064
Operating expense		5,645	2,969	11,655	5,560
Operating income (loss)		(2,357)	268	(5,678)	504
Net income (loss) before noncontrolling interest		(2,151)	4,504	(5,661)	4,226
Depreciation and amortization		384	441	766	900
Senior note and other interest expense		544	541	1,088	1,173
Income tax expense (benefit) in net income		(582)	2,056	(1,654)	1,831
Assets		$ 50,407	$ 72,619	$ 50,407	$ 72,619
[1]	* The “All Other” category includes the accounts of SJW Group and Hydro Sub, Inc. on a stand-alone basis

Fair Value Measurement (Details

Fair Value Measurement (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017	Dec. 31, 2017
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term debt	$ 431,258		$ 431,258		$ 431,092
Unrealized gain (loss) on California Water Service Group stock	140	$ 0	(527)	$ 0
Significant Observable Inputs
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term debt, fair value	492,886		492,886		537,840
Quoted Prices in Active Markets for Identical Assets
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Investment in California Water Service Group	$ 3,207		$ 3,207		$ 4,535

Regulatory Rate Filings (Detail

Regulatory Rate Filings (Details) - USD ($) $ in Thousands	Jul. 26, 2018	Jun. 13, 2018	Jun. 07, 2018	Dec. 31, 2018	Jan. 04, 2018
Public Utilities, General Disclosures [Line Items]
Regulatory Rate Filings, Requested Rate Increase, Year One					$ 34,288
Regulatory Rate Filings, Requested Rate Increase as Percentage of Total Revenue at Time of Request, Year One					9.76%
Regulatory Rate Filings, Requested Rate Increase, Year Two					$ 14,232
Regulatory Rate Filings, Proposed Rate Increase, Percent of Authorized Revenue, Year Two					3.70%
Regulatory Rate Filings, Requested Rate Increase, Year Three					$ 20,582
Regulatory Rate Filings, Requested Rate Increase, Percent of Authorized Revenue, Year Three					5.17%
Memorandum Account, Authorized Recovery					$ 20,725
Public Utilities, Requested Rate Increase (Decrease), Amount		$ 13,732	$ (14,801)
Public Utilities, Requested Rate Increase (Decrease), Percentage		3.75%	(3.89%)
Subsequent Event [Member]
Public Utilities, General Disclosures [Line Items]
Public Utilities, Requested Rate Increase (Decrease), Amount	$ 3,155
Public Utilities, Requested Rate Increase (Decrease), Percentage	0.83%
Scenario, Forecast [Member] | SJWTX, Inc. [Member]
Public Utilities, General Disclosures [Line Items]
Public Utilities, Approved Rate Decrease, Amount				$ 1,023

Balancing and Memorandum Acco38

Balancing and Memorandum Account Recovery Procedures (Details) - USD ($) $ in Thousands		3 Months Ended		6 Months Ended
		Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Balancing and Memorandum Revenue Account [Roll Forward]
Beginning Balance		$ 19,676	$ 24,067	$ 21,706	$ 25,909
Regulatory Asset Increase (Decrease)		(408)	10,252	(2,438)	14,587
Refunds (Collections)		8	(5,303)	8	(11,556)
Surcharge Offset		0	0	0	76
Ending Balance		19,276	29,016	19,276	29,016
Balancing and Memorandum Cost Recovery Account [Roll Forward]
Beginning Balance		5,899	0	6,220	0
Regulatory Asset Increase (Decrease)		1,351	0	1,030	0
Refunds (Collections)		0	0	0	0
Surcharge Offset		0	0	0	0
Ending Balance		7,250	0	7,250	0
Balancing and Memorandum Account [Roll Forward]
Beginning Balance		25,575	24,067	27,926	25,909
Regulatory Asset Increase (Decrease)		943	10,252	(1,408)	14,587
Refunds (Collections)		8	(5,303)	8	(11,556)
Surcharge Offset		0	0	0	76
Ending Balance		26,526	29,016	26,526	29,016
Regulatory Balancing and Memorandum Accounts, Net Under-Collected		3,900		3,900
2014-2016 WCMA
Balancing and Memorandum Revenue Account [Roll Forward]
Beginning Balance		270	398	190	1,589
Regulatory Asset Increase (Decrease)		93	3,206	173	4,654
Refunds (Collections)		2	(556)	2	(1,788)
Surcharge Offset		0	(45)	0	(1,452)
Ending Balance		365	3,003	365	3,003
2017 WCMA
Balancing and Memorandum Revenue Account [Roll Forward]
Beginning Balance	[1]	6,785	0	6,489	0
Regulatory Asset Increase (Decrease)	[1]	127	4,989	423	7,049
Refunds (Collections)	[1]	0	0	0	0
Surcharge Offset	[1]	0	(3,988)	0	(6,048)
Ending Balance	[1]	6,912	1,001	6,912	1,001
2018 WCMA
Balancing and Memorandum Revenue Account [Roll Forward]
Beginning Balance	[1]	(708)	0	0	0
Regulatory Asset Increase (Decrease)	[1]	3,711	0	3,003	0
Refunds (Collections)	[1]	0	0	0	0
Surcharge Offset	[1]	0	0	0	0
Ending Balance	[1]	3,003	0	3,003	0
Balancing and Memorandum Account [Roll Forward]
Memorandum Account, Revenue Increase (Reduction)		(4,118)		(3,410)
2012 General Rate Case true-up
Balancing and Memorandum Revenue Account [Roll Forward]
Beginning Balance		11,320	18,424	11,320	20,682
Regulatory Asset Increase (Decrease)		0	0	0	0
Refunds (Collections)		4	(2,659)	4	(4,917)
Surcharge Offset		0	0	0	0
Ending Balance		11,324	15,765	11,324	15,765
2015 General Rate Case true-up
Balancing and Memorandum Revenue Account [Roll Forward]
Beginning Balance		115	4,097	115	5,528
Regulatory Asset Increase (Decrease)		0	0	0	0
Refunds (Collections)		2	(1,686)	2	(3,117)
Surcharge Offset		0	0	0	0
Ending Balance		117	2,411	117	2,411
Cost of capital
Balancing and Memorandum Revenue Account [Roll Forward]
Beginning Balance		(1,309)	(459)	(144)	(817)
Regulatory Asset Increase (Decrease)		(198)	0	(1,363)	0
Refunds (Collections)		0	315	0	673
Surcharge Offset		0	0	0	0
Ending Balance		(1,507)	(144)	(1,507)	(144)
Tax memorandum
Balancing and Memorandum Revenue Account [Roll Forward]
Beginning Balance		(933)	0	0	0
Regulatory Asset Increase (Decrease)		(4,563)	0	(5,496)	0
Refunds (Collections)		0	0	0	0
Surcharge Offset		0	0	0	0
Ending Balance		(5,496)	0	(5,496)	0
Drought surcharges
Balancing and Memorandum Revenue Account [Roll Forward]
Beginning Balance		0	(5,054)	0	(7,688)
Regulatory Asset Increase (Decrease)		0	0	0	0
Refunds (Collections)		0	60	0	(773)
Surcharge Offset		0	4,033	0	7,500
Ending Balance		0	(961)	0	(961)
Cost-Recovery Accounts [Member]
Balancing and Memorandum Revenue Account [Roll Forward]
Beginning Balance		0	3,145	0	3,181
Regulatory Asset Increase (Decrease)		0	1,631	0	2,001
Refunds (Collections)		0	(369)	0	(775)
Surcharge Offset		0	0	0	0
Ending Balance		0	4,407	0	4,407
Water supply costs
Balancing and Memorandum Cost Recovery Account [Roll Forward]
Beginning Balance		8,197	0	8,679	0
Regulatory Asset Increase (Decrease)		1,190	0	708	0
Refunds (Collections)		0	0	0	0
Surcharge Offset		0	0	0	0
Ending Balance		9,387	0	9,387	0
Pension
Balancing and Memorandum Cost Recovery Account [Roll Forward]
Beginning Balance		(2,298)	0	(2,459)	0
Regulatory Asset Increase (Decrease)		161	0	322	0
Refunds (Collections)		0	0	0	0
Surcharge Offset		0	0	0	0
Ending Balance		(2,137)	0	(2,137)	0
All others
Balancing and Memorandum Revenue Account [Roll Forward]
Beginning Balance		4,136	3,516	3,736	3,434
Regulatory Asset Increase (Decrease)		422	426	822	883
Refunds (Collections)		0	(408)	0	(859)
Surcharge Offset		0	0	0	76
Ending Balance		4,558	$ 3,534	4,558	3,534
2017 WCMA Reserve Recorded
Balancing and Memorandum Account [Roll Forward]
Memorandum Account, Revenue Increase (Reduction)				(938)	$ (276)
2018 WCMA Reserve Recorded
Balancing and Memorandum Account [Roll Forward]
Memorandum Account, Revenue Increase (Reduction)		$ (407)		$ (407)
[1]	As of June 30, 2018, the reserve balances for the 2017 and 2018 WCMA were $938 and $407, respectively, which have been netted from the balances above. As of June 30, 2017, the reserve balance for the 2017 WCMA was $276 which has been netted from the balance above.

Regulatory Assets and Liabili39

Regulatory Assets and Liabilities (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017	Dec. 31, 2017
Regulatory Assets [Line Items]
Net income (loss) before noncontrolling interest	$ 12,871	$ 20,584	$ 14,156	$ 24,255
Net Regulatory Assets	98,332		98,332		$ 99,554
Total regulatory liability in Consolidated Balance Sheets	61,639		61,639		62,476
Deferred Income Tax Charge [Member]
Regulatory Assets [Line Items]
Regulatory Liabilities	61,639		61,639		62,476
Postretirement pensions and other medical benefits
Regulatory Assets [Line Items]
Regulatory assets:	68,556		68,556		68,556
Balancing and memorandum accounts, net
Regulatory Assets [Line Items]
Regulatory assets:	26,526		26,526		27,925
Other, net
Regulatory Assets [Line Items]
Regulatory assets:	$ 3,250		$ 3,250		$ 3,073

California Water Service Grou40

California Water Service Group Stock (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Investments, Debt and Equity Securities [Abstract]
Available for Sale Marketable Security, Shares Sold			17,660
Available-for-sale Securities, Gross Realized Gains (Losses), Sale Proceeds			$ 716
Fees Incurred on Sale of Available for Sale Securities			2
Available-for-sale Securities, Gross Realized Gain (Loss)	$ 0	$ 0	(87)	$ 0
Available for Sales Securities, Tax on Realized Gain			(24)
Gain (Loss) on Sale of Securities, Net			$ (63)
Available for Sale Marketable Security, Shares Held	82,340		82,340

SJW Group and Connecticut Water

SJW Group and Connecticut Water Service Merger Agreement (Details) - $ / shares	Mar. 14, 2018	Jun. 30, 2018	Dec. 31, 2017
Business Combinations [Abstract]
Conversion rate of CTWS shares to SJW Group (in shares)	1.1375
SJW Group common stock, par value (usd per share)		$ 0.001	$ 0.001

Subsequent Event (Details)

Subsequent Event (Details) - Deer Creek Ranch Water Co., LLC [Member] - SJWTX, Inc. [Member] - Subsequent Event [Member] $ in Thousands	Jul. 02, 2018USD ($)aservice_connection
Subsequent Event [Line Items]
Payment to acquire business | $	$ 2,700
Number of service connections acquired | service_connection	750
Area of land acquired (in acres) | a	1,191