SJW (SJW) 10-Q 8 May 18 2018 Q1 Quarterly report Financial data

Document and Entity Information

Document and Entity Information Document - shares	3 Months Ended
	Mar. 31, 2018	May 04, 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	Mar. 31, 2018
Document Fiscal Year Focus	2,018
Document Fiscal Period Focus	Q1
Amendment Flag	false
Entity Common Stock, Shares Outstanding		20,594,486

Condensed Consolidated Statemen

Condensed Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Income Statement [Abstract]
REVENUE	$ 75,042	$ 69,045
Production Expenses:
Purchased water	15,416	13,924
Power	1,268	1,287
Groundwater extraction charges	9,532	7,410
Other production expenses	4,212	3,859
Total production expenses	30,428	26,480
Administrative and general	11,568	11,149
Maintenance	4,460	3,898
Property taxes and other non-income taxes	3,866	3,695
Depreciation and amortization	13,583	12,119
Merger related expenses	3,806	0
Total operating expense	67,711	57,341
OPERATING INCOME	7,331	11,704
OTHER (EXPENSE) INCOME:
Interest on long-term debt and other interest expense	(6,052)	(6,057)
Pension non-service cost	(583)	(871)
Unrealized loss on California Water Service Group stock	(667)	0
Other, net	676	463
Income before income taxes	705	5,239
Provision for income taxes	(580)	1,568
SJW GROUP NET INCOME	1,285	3,671
Other comprehensive income, net of tax:
Unrealized gain on investment	0	116
SJW GROUP COMPREHENSIVE INCOME	$ 1,285	$ 3,787
SJW GROUP EARNINGS PER SHARE
Basic (usd per share)	$ 0.06	$ 0.18
Diluted (usd per share)	0.06	0.18
DIVIDENDS PER SHARE (usd per share)	$ 0.28	$ 0.22
WEIGHTED AVERAGE SHARES OUTSTANDING
Basic (shares)	20,561,329	20,485,968
Diluted (shares)	20,701,031	20,655,239

Condensed Consolidated Balance

Condensed Consolidated Balance Sheets - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Utility plant:
Land	$ 17,831	$ 17,831
Depreciable plant and equipment	1,733,449	1,714,228
Construction in progress	54,933	45,851
Intangible assets	15,567	14,413
Utility plant, gross	1,821,780	1,792,323
Less accumulated depreciation and amortization	566,844	553,059
Utility plant, net	1,254,936	1,239,264
Real estate investments	56,213	56,213
Less accumulated depreciation and amortization	11,431	11,132
Total	44,782	45,081
CURRENT ASSETS:
Cash and cash equivalents	6,954	7,799
Accounts receivable:
Customers, net of allowances for uncollectible accounts	18,326	17,305
Income tax	7,072	7,981
Other	1,578	1,118
Accrued unbilled utility revenue	22,608	27,905
Other current assets	4,522	4,750
Current assets	61,060	66,858
OTHER ASSETS:
Investment in California Water Service Group	3,067	4,535
Net regulatory assets, less current portion	97,293	99,554
Other	2,736	2,709
Other assets	103,096	106,798
Assets	1,463,874	1,458,001
Stockholders’ equity:
Common stock, $0.001 par value; authorized 36,000,000 shares; issued and outstanding shares 20,585,136 on March 31, 2018 and 20,520,856 on December 31, 2017	21	21
Additional paid-in capital	83,986	84,866
Retained earnings	373,823	376,119
Accumulated other comprehensive income	0	2,203
Total stockholders’ equity	457,830	463,209
Long-term debt, less current portion	431,175	431,092
Capitalization, Long-term Debt and Equity	889,005	894,301
CURRENT LIABILITIES:
Line of credit	39,000	25,000
Accrued groundwater extraction charges, purchased water and power	11,692	14,382
Accounts payable	22,482	22,960
Accrued interest	7,400	6,869
Accrued property taxes and other non-income taxes	2,780	1,904
Accrued payroll	3,620	6,011
Other current liabilities	8,386	7,926
Current liabilities	95,360	85,052
DEFERRED INCOME TAXES	84,442	85,795
ADVANCES FOR CONSTRUCTION	82,611	83,695
CONTRIBUTIONS IN AID OF CONSTRUCTION	162,443	160,830
POSTRETIREMENT BENEFIT PLANS	74,735	72,841
REGULATORY LIABILITY	62,205	62,476
OTHER NONCURRENT LIABILITIES	13,073	13,011
COMMITMENTS AND CONTINGENCIES	0	0
Capitalization and liabilities	$ 1,463,874	$ 1,458,001

Condensed Consolidated Balance4

Condensed Consolidated Balance Sheets (Parenthetical) - $ / shares	Mar. 31, 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)	20,585,136	20,520,856
Common stock, shares outstanding (shares)	20,585,136	20,520,856

Condensed Consolidated Stateme5

Condensed Consolidated Statements of Cash Flows - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
OPERATING ACTIVITIES:
Net income	$ 1,285	$ 3,671
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	14,160	12,646
Deferred income taxes	(1,383)	1,595
Share-based compensation	487	586
Unrealized loss on California Water Service Group stock	667	0
Loss on sale of California Water Service Group stock	87	0
Changes in operating assets and liabilities:
Accounts receivable and accrued unbilled utility revenue	4,530	6,015
Accounts payable and other current liabilities	784	557
Accrued groundwater extraction charges, purchased water and power	(2,690)	(454)
Tax payable and receivable, and other accrued taxes	2,465	1,090
Postretirement benefits	1,894	1,915
Regulatory assets and liability related to balancing and memorandum accounts	2,350	1,917
Other changes, net	(2,054)	(1,296)
NET CASH PROVIDED BY OPERATING ACTIVITIES	22,582	28,242
INVESTING ACTIVITIES:
Company-funded	(28,961)	(27,745)
Contributions in aid of construction	(1,468)	(1,646)
Additions to real estate investments	0	(62)
Payments to retire utility plant, net of salvage	(1,134)	(397)
Payments for business/asset acquisition and water rights	0	1,101
NET CASH USED IN INVESTING ACTIVITIES	(31,563)	(30,951)
FINANCING ACTIVITIES:
Borrowings on line of credit	14,000	0
Repayments of line of credit	0	(14,200)
Repayments of long-term borrowings	0	(32)
Dividends paid	(5,754)	(4,456)
Receipts of advances and contributions in aid of construction	2,148	3,924
Refunds of advances for construction	(537)	(532)
Other changes, net	(1,721)	(245)
NET CASH PROVIDED BY (USED IN) FINANCING ACTIVITIES	8,136	(15,541)
NET CHANGE IN CASH AND CASH EQUIVALENTS	(845)	(18,250)
CASH, CASH EQUIVALENTS AND RESTRICTED CASH, BEGINNING OF PERIOD	7,799	25,350
CASH AND CASH EQUIVALENTS, END OF PERIOD	6,954	7,100
Cash paid during the period for:
Interest	6,042	6,044
Income taxes	85	0
Supplemental disclosure of non-cash activities:
Change in accrued payables for construction costs capitalized	(790)	1,634
Utility property installed by developers	590	243
RECONCILIATION TO CONSOLIDATED BALANCE SHEETS:
Cash and cash equivalents	6,954	7,092
Restricted cash	$ 0	$ 8

General

General	3 Months Ended
	Mar. 31, 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 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 our 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, amortization of 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 an amortization 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 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 for 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 this ASU 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 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 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, certain water use restrictions remain in place as well a conservation target by SCVWD at 20% . To encourage conservation, San Jose Water Company received approval from the CPUC to institute 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 ASU 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 March 31, 2018 2017 Revenue from contracts with customers $ 75,869 68,567 Alternative revenue programs, net - WCMA (332 ) 2,276 Other balancing and memorandum accounts revenue, net * (1,836 ) (3,361 ) Rental income 1,341 1,563 $ 75,042 69,045 * The amount reflected for three months ended March 31, 2018 , excludes a further reduction of $321 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 to 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 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 March 31, 2018 , and 2017 , 1,162 and 2,006 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 March 31, 2018 , and 2017 , the amounts allocated to administrative and general expense were $577 and $527 , respectively.

Equity Plans

Equity Plans	3 Months Ended
	Mar. 31, 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 share-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 shares, or other share-based awards. As of March 31, 2018 , the remaining number of shares available under the Incentive Plan was 890,179 , and an additional 191,547 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 months ended March 31, 2018 , and 2017 . Three months ended March 31, 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 372 486 Total compensation costs charged to income $ 487 586 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 share-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 March 31, 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 share-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 March 31, 2018 , management believes that it is probable 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 awards was estimated utilizing the Monte Carlo valuation model, using the fair value of SJW Group’s common stock with the effect of market condition and no dividend yield on the date of grant, and assumes the performance goals will be attained. Share-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. As of March 31, 2018 , the total unrecognized compensation costs related to restricted and deferred restricted stock plans was $2,394 . This cost is expected to be recognized over a remaining weighted average period of 1.50 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 $53 and $63 for the three months ended March 31, 2018 , and 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 $107 . This cost is expected to be recognized during the second and third quarters of 2018.

Real Estate Investments

Real Estate Investments	3 Months Ended
	Mar. 31, 2018
Real Estate Investments, Net [Abstract]
REAL ESTATE INVESTMENTS	Real Estate Investments The major components of real estate investments as of March 31, 2018 , and December 31, 2017 are as follows: March 31, December 31, Land $ 13,262 13,262 Buildings and improvements 42,951 42,951 Subtotal 56,213 56,213 Less: accumulated depreciation and amortization 11,431 11,132 Total $ 44,782 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 .

Defined Benefit Plan

Defined Benefit Plan	3 Months Ended
	Mar. 31, 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 months ended March 31, 2018 , and 2017 are as follows: Three months ended March 31, 2018 2017 Service cost $ 1,596 1,330 Interest cost 1,877 1,903 Other cost 1,133 1,038 Expected return on assets (2,427 ) (2,070 ) $ 2,179 2,201 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 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. As of March 31, 2017 , utility plant included $128 of capitalized pension non-service cost. The components of net periodic benefit cost have been recorded in the consolidated statements of comprehensive income as follows: Three months ended March 31, 2018 2017 Other production expenses $ 423 348 Administrative and general expense 895 745 Maintenance expense 278 237 Pension non-service costs 583 871 $ 2,179 2,201 The following tables summarize the fair values of plan assets by major categories as of March 31, 2018 , and December 31, 2017 : Fair Value Measurements at March 31, 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 $ 5,928 $ 5,928 $ — $ — Actively Managed (a): All Cap Equity Russell 3000 Value 6,190 6,151 39 — U.S. Large Cap Equity Russell 1000, Russell 1000 Growth, Russell 1000 Value 50,495 50,495 — — U.S. Mid Cap Equity Russell Mid Cap, Russell Mid Cap Growth, Russell Mid Cap Value 9,376 9,376 — — U.S. Small Cap Equity Russell 2000, Russell 2000 Growth, Russell 2000 Value 9,306 9,306 — — Non-U.S. Large Cap Equity MSCI EAFE 5,949 5,949 — — REIT NAREIT - Equity REIT’S 5,864 — 5,864 — Fixed Income (b) (b) 44,873 — 44,873 — Total $ 137,981 $ 87,205 $ 50,776 $ — 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 months ended March 31, 2018 , there have been no contributions to the pension plans and Social Welfare Plan.

Segment and Non-Tariffed Busine

Segment and Non-Tariffed Business Reporting	3 Months Ended
	Mar. 31, 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 is 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 up to November 2017 Texas Water Alliance Limited, 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 March 31, 2018 Water Utility Services Real Estate Services All Other* SJW Group Regulated Non-tariffed Non-tariffed Non-tariffed Regulated Non-tariffed Total Operating revenue $ 72,353 1,348 1,341 — 72,353 2,689 75,042 Operating expense 61,701 888 849 4,273 61,701 6,010 67,711 Operating income (loss) 10,652 460 492 (4,273 ) 10,652 (3,321 ) 7,331 Net income (loss) 4,795 331 356 (4,197 ) 4,795 (3,510 ) 1,285 Depreciation and amortization 13,201 83 299 — 13,201 382 13,583 Senior note, mortgage and other interest expense 5,508 — — 544 5,508 544 6,052 Income tax expense (benefit) in net income 492 129 94 (1,295 ) 492 (1,072 ) (580 ) Assets $ 1,413,300 3,690 47,380 (496 ) 1,413,300 50,574 1,463,874 For Three Months Ended March 31, 2017 Water Utility Services Real Estate Services All Other* SJW Group Regulated Non-tariffed Non-tariffed Non-tariffed Regulated Non-tariffed Total Operating revenue $ 66,218 1,264 1,563 — 66,218 2,827 69,045 Operating expense 54,750 831 948 812 54,750 2,591 57,341 Operating income (loss) 11,468 433 615 (812 ) 11,468 236 11,704 Net income (loss) 3,949 172 360 (810 ) 3,949 (278 ) 3,671 Depreciation and amortization 11,660 136 323 — 11,660 459 12,119 Senior note, mortgage and other interest expense 5,425 — 65 567 5,425 632 6,057 Income tax expense (benefit) in net income 1,793 137 128 (490 ) 1,793 (225 ) 1,568 Assets $ 1,360,599 18,247 54,269 2,662 1,360,599 75,178 1,435,777 * The “All Other” category includes the accounts of SJW Group and Hydro Sub, Inc. on a stand-alone basis. For the three months ended March 31, 2018 , Hydro Sub, Inc. had recorded no revenue or expenses and as of March 31, 2018 , held no assets or incurred no liabilities. For the three months ended March 31, 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	3 Months Ended
	Mar. 31, 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	3 Months Ended
	Mar. 31, 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 March 31, 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 March 31, 2018 , approximates their carrying value as reported on the condensed consolidated balance sheets. The fair value of such financial instruments are determined using the income approach based on the present value of estimated future cash flows. There have been no changes in valuation technique during the three months ended March 31, 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 $512,151 and $537,840 as of March 31, 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 $ 431,175 and $ 431,092 as of March 31, 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 March 31, 2018 , and December 31, 2017 , the fair value of the company’s investment in California Water Service Group was $3,067 and $4,535 , respectively, and would be categorized as Level 1 of the fair value hierarchy. For the three months ended March 31, 2018 , SJW Group recognized an unrealized loss of $667 due to the change in fair value of the company’s investment in California Water Service Group.

Regulatory Rate Filings

Regulatory Rate Filings	3 Months Ended
	Mar. 31, 2018
Regulated Operations [Abstract]
Regulatory Rate Filings	Regulatory Rate Filings On November 15, 2017, San Jose Water Company filed Advice Letter No. 513/513A with the CPUC requesting a revenue increase of $15,670 , or 4.22% , for the 2018 escalation year included in the 2015 General Rate Case. This request was approved and the new rates became effective on January 1, 2018. On November 29, 2017, San Jose Water Company filed Advice Letter No. 514 with the CPUC requesting to adjust the Utilities Reimbursement Account User Fees as directed by CPUC Resolution M-4832. The reimbursement fee was reduced from 1.44% to 1.40% . This request was approved and the new fee became effective on January 1, 2018. San Jose Water Company filed Advice Letter No. 515 on December 28, 2017, with the CPUC requesting authorization to establish the 2018 Tax Accounting Memorandum Account. This memorandum account will capture any changes to revenue requirement resulting from the impact of the Tax Act signed into law December 22, 2017. This request became effective on January 1, 2018. On January 6, 2017, San Jose Water Company filed Advice Letter No. 501 with the CPUC requesting authorization to implement a sales reconciliation mechanism to better conform to water forecasts authorized in the last general rate case to recorded consumption for the period of October 2015 through September 2016. The CPUC ordered all Class A and B water utilities that have a five percent or greater divergence between authorized and actual sales during declared drought years to consider requesting a sales reconciliation mechanism to better conform to sale forecasts authorized in the last general rate case to recorded consumption. On May 3, 2017, the CPUC rejected the filing citing the end of a drought and the improved California water supply conditions. On May 10, 2017, San Jose Water Company formally requested the CPUC ’ s review of the rejection. On August 25, 2017, the CPUC’s Water Division released Proposed Resolution W-5150 affirming its rejection of Advice Letter No. 501. On September 20, 2017, Revision 1 to Proposed Resolution W-5150 was released by the Water Division. A revised resolution, Proposed Resolution W-5153, was circulated on December 8, 2017, for comment and also affirmed the rejection of Advice Letter No. 501. Subsequently, the resolution to reject Advice Letter No. 501 was approved by CPUC on January 11, 2018. As required by the CPUC, on April 3, 2017, San Jose Water Company filed an application requesting authority to increase its authorized Cost of Capital for the period from January 1, 2018 through December 31, 2020. On March 22, 2018, the CPUC approved a new cost of capital for San Jose Water Company in Decision 18-03-035 that lowers the rate of return from 8.09% to 7.64% thereby reducing the 2018 revenue requirement by $5,843 or 1.57% . On March 22, 2018, San Jose Water Company filed Advice Letter No. 518 with the CPUC requesting authorization to adjust water rates to reflect the decision effective March 22, 2018. On January 4, 2018, San Jose Water Company filed General Rate Case Application No. 18-01-004 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. 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. The application is a year-long review process and new rates, if approved, are expected to be 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. On March 23, 2018, San Jose Water Company filed Advice Letter No. 519 with the CPUC requesting authorization to update the Rule 15 income tax provisions as a result of the recent changes to the federal tax laws. This advice letter has no impact on water rates and was effective January 1, 2018. The Public Utilities Commission of Texas (“PUCT”) has directed CLWSC (as well as other Class A water utilities in Texas) to quantify all of the impacts of the Tax Act and make rate adjustments reflecting these 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 review on April 19, 2018. If adopted as proposed, the revenue requirement for CLWSC will be reduced by about $745 for 2018, with new rates becoming effective for billings on or about May 1, 2018. As of March 31, 2018 , CLWSC has recorded a Tax Act regulatory liability in the amount of $139 . On May 4, 2018, SJW Group and CTWS filed with the Connecticut Public Utilities Regulatory Authority and the Maine Public Utilities Commission applications for the approval of the proposed merger (see discussion on the proposed merger at Note 12).

Balancing and Memorandum Accoun

Balancing and Memorandum Account Recovery Procedures	3 Months Ended
	Mar. 31, 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 a regulatory liability of $708 due to excess revenues accumulated in the 2018 WCMA account for the three months ended March 31, 2018 . Since the balance represents an amount due to customers, San Jose Water Company recorded a regulatory liability for the amount with a corresponding reduction to revenues. The amount has 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 $1,165 in the cost of capital memorandum account for the three months ended March 31, 2018 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 has 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 has 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 $933 in the tax memorandum account for the three months ended March 31, 2018 , 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 March 31, 2018 Three months ended March 31, 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 79 1 — 270 $ 1,589 1,448 (1,232 ) (1,407 ) 398 2017 WCMA* 6,489 296 — — 6,785 — 2,060 — (2,060 ) — 2018 WCMA — (708 ) — — (708 ) — — — — — 2012 General Rate Case true-up 11,319 — 1 — 11,320 20,682 — (2,258 ) — 18,424 2015 General Rate Case true-up 115 — — — 115 5,528 — (1,431 ) — 4,097 Cost of capital memorandum account (144 ) (1,165 ) — — (1,309 ) (817 ) — 358 — (459 ) Tax memorandum account — (933 ) — — (933 ) — — — — — Drought surcharges — — — — — (7,688 ) — (833 ) 3,467 (5,054 ) Water supply costs — — — — — 5,190 197 297 — 5,684 Pension — — — — — (2,009 ) 173 (703 ) — (2,539 ) All others 3,736 400 — — 4,136 3,434 457 (451 ) 76 3,516 Total revenue accounts: $ 21,705 (2,031 ) 2 — 19,676 $ 25,909 4,335 (6,253 ) 76 24,067 Cost-recovery accounts: Water supply costs 8,679 (482 ) — — 8,197 — — — — — Pension (2,459 ) 161 — — (2,298 ) — — — — — Total cost-recovery accounts $ 6,220 (321 ) — — 5,899 $ — — — — — Total $ 27,925 (2,352 ) 2 — 25,575 $ 25,909 4,335 (6,253 ) 76 24,067 * As of March 31, 2018 and 2017 , the reserve balance for the 2017 WCMA was $1,022 and $0 , which has been netted from the balance above. As of March 31, 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 $3,910 . 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	3 Months Ended
	Mar. 31, 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 March 31, 2018 and December 31, 2017 : March 31, 2018 December 31, 2017 Regulatory assets: Postretirement pensions and other medical benefits $ 68,556 68,556 Balancing and memorandum accounts, net 25,575 27,925 Other, net 3,162 3,073 Total regulatory assets, net in Consolidated Balance Sheets $ 97,293 99,554 Regulatory liability: Income tax temporary differences, net $ 62,205 62,476 Total regulatory liability in Consolidated Balance Sheets $ 62,205 62,476

California Water Service Group

California Water Service Group Stock California Water Service Group Stock	3 Months Ended
	Mar. 31, 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 . The proceeds of the sale was recorded as a receivable on SJW Group’s Consolidated Balance Sheets as of March 31, 2018 . As of March 31, 2018 , SJW Group held 82,340 shares of California Water Service Group. 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	3 Months Ended
	Mar. 31, 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 in an all-stock transaction (the “Merger Agreement”). Under the terms of the agreement, Hydro Sub, Inc. will merge with and into CTWS (the “Merger”), with CTWS surviving the Merger as a wholly-owned subsidiary of the company. 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 (each, a “CTWS Common Share”), other than CTWS Common Shares directly or indirectly owned by the company, Merger Sub, 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 stockholders, approval by certain regulators, the listing on the New York Stock Exchange of Company Common Shares 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; 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.

Legal Proceedings

Legal Proceedings	3 Months Ended
	Mar. 31, 2018
Commitments and Contingencies Disclosure [Abstract]
LEGAL PROCEEDINGS	Legal Proceedings 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.

General (Policies)

General (Policies)	3 Months Ended
	Mar. 31, 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 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 our 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, amortization of 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 an amortization 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 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 for 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 this ASU 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]	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 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 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.
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)	3 Months Ended
	Mar. 31, 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 March 31, 2018 2017 Revenue from contracts with customers $ 75,869 68,567 Alternative revenue programs, net - WCMA (332 ) 2,276 Other balancing and memorandum accounts revenue, net * (1,836 ) (3,361 ) Rental income 1,341 1,563 $ 75,042 69,045 * The amount reflected for three months ended March 31, 2018 , excludes a further reduction of $321 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 to revenue. For further discussion, please see Note 9.

Equity Plans (Tables)

Equity Plans (Tables)	3 Months Ended
	Mar. 31, 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 months ended March 31, 2018 , and 2017 . Three months ended March 31, 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 372 486 Total compensation costs charged to income $ 487 586 Proceeds from ESPP $ 653 570

Real Estate Investments (Tables

Real Estate Investments (Tables)	3 Months Ended
	Mar. 31, 2018
Real Estate Investments, Net [Abstract]
Schedule of Real Estate Investments	The major components of real estate investments as of March 31, 2018 , and December 31, 2017 are as follows: March 31, December 31, Land $ 13,262 13,262 Buildings and improvements 42,951 42,951 Subtotal 56,213 56,213 Less: accumulated depreciation and amortization 11,431 11,132 Total $ 44,782 45,081

Defined Benefit Plan (Tables)

Defined Benefit Plan (Tables)	3 Months Ended
	Mar. 31, 2018
Retirement Benefits [Abstract]
Schedule of Net Benefit Costs	As of March 31, 2017 , utility plant included $128 of capitalized pension non-service cost. The components of net periodic benefit cost have been recorded in the consolidated statements of comprehensive income as follows: Three months ended March 31, 2018 2017 Other production expenses $ 423 348 Administrative and general expense 895 745 Maintenance expense 278 237 Pension non-service costs 583 871 $ 2,179 2,201 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 months ended March 31, 2018 , and 2017 are as follows: Three months ended March 31, 2018 2017 Service cost $ 1,596 1,330 Interest cost 1,877 1,903 Other cost 1,133 1,038 Expected return on assets (2,427 ) (2,070 ) $ 2,179 2,201
Schedule of Allocation of Plan Assets	The following tables summarize the fair values of plan assets by major categories as of March 31, 2018 , and December 31, 2017 : Fair Value Measurements at March 31, 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 $ 5,928 $ 5,928 $ — $ — Actively Managed (a): All Cap Equity Russell 3000 Value 6,190 6,151 39 — U.S. Large Cap Equity Russell 1000, Russell 1000 Growth, Russell 1000 Value 50,495 50,495 — — U.S. Mid Cap Equity Russell Mid Cap, Russell Mid Cap Growth, Russell Mid Cap Value 9,376 9,376 — — U.S. Small Cap Equity Russell 2000, Russell 2000 Growth, Russell 2000 Value 9,306 9,306 — — Non-U.S. Large Cap Equity MSCI EAFE 5,949 5,949 — — REIT NAREIT - Equity REIT’S 5,864 — 5,864 — Fixed Income (b) (b) 44,873 — 44,873 — Total $ 137,981 $ 87,205 $ 50,776 $ — 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 Busi24

Segment and Non-Tariffed Business Reporting (Tables)	3 Months Ended
	Mar. 31, 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 March 31, 2018 Water Utility Services Real Estate Services All Other* SJW Group Regulated Non-tariffed Non-tariffed Non-tariffed Regulated Non-tariffed Total Operating revenue $ 72,353 1,348 1,341 — 72,353 2,689 75,042 Operating expense 61,701 888 849 4,273 61,701 6,010 67,711 Operating income (loss) 10,652 460 492 (4,273 ) 10,652 (3,321 ) 7,331 Net income (loss) 4,795 331 356 (4,197 ) 4,795 (3,510 ) 1,285 Depreciation and amortization 13,201 83 299 — 13,201 382 13,583 Senior note, mortgage and other interest expense 5,508 — — 544 5,508 544 6,052 Income tax expense (benefit) in net income 492 129 94 (1,295 ) 492 (1,072 ) (580 ) Assets $ 1,413,300 3,690 47,380 (496 ) 1,413,300 50,574 1,463,874 For Three Months Ended March 31, 2017 Water Utility Services Real Estate Services All Other* SJW Group Regulated Non-tariffed Non-tariffed Non-tariffed Regulated Non-tariffed Total Operating revenue $ 66,218 1,264 1,563 — 66,218 2,827 69,045 Operating expense 54,750 831 948 812 54,750 2,591 57,341 Operating income (loss) 11,468 433 615 (812 ) 11,468 236 11,704 Net income (loss) 3,949 172 360 (810 ) 3,949 (278 ) 3,671 Depreciation and amortization 11,660 136 323 — 11,660 459 12,119 Senior note, mortgage and other interest expense 5,425 — 65 567 5,425 632 6,057 Income tax expense (benefit) in net income 1,793 137 128 (490 ) 1,793 (225 ) 1,568 Assets $ 1,360,599 18,247 54,269 2,662 1,360,599 75,178 1,435,777 * The “All Other” category includes the accounts of SJW Group and Hydro Sub, Inc. on a stand-alone basis. For the three months ended March 31, 2018 , Hydro Sub, Inc. had recorded no revenue or expenses and as of March 31, 2018 , held no assets or incurred no liabilities. For the three months ended March 31, 2017 , the “All Other” category includes the accounts of SJW Group on a stand-alone basis.

Balancing and Memorandum Acco25

Balancing and Memorandum Account Recovery Procedures (Tables)	3 Months Ended
	Mar. 31, 2018
Regulated Operations [Abstract]
Public Utilities General Disclosures	Three months ended March 31, 2018 Three months ended March 31, 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 79 1 — 270 $ 1,589 1,448 (1,232 ) (1,407 ) 398 2017 WCMA* 6,489 296 — — 6,785 — 2,060 — (2,060 ) — 2018 WCMA — (708 ) — — (708 ) — — — — — 2012 General Rate Case true-up 11,319 — 1 — 11,320 20,682 — (2,258 ) — 18,424 2015 General Rate Case true-up 115 — — — 115 5,528 — (1,431 ) — 4,097 Cost of capital memorandum account (144 ) (1,165 ) — — (1,309 ) (817 ) — 358 — (459 ) Tax memorandum account — (933 ) — — (933 ) — — — — — Drought surcharges — — — — — (7,688 ) — (833 ) 3,467 (5,054 ) Water supply costs — — — — — 5,190 197 297 — 5,684 Pension — — — — — (2,009 ) 173 (703 ) — (2,539 ) All others 3,736 400 — — 4,136 3,434 457 (451 ) 76 3,516 Total revenue accounts: $ 21,705 (2,031 ) 2 — 19,676 $ 25,909 4,335 (6,253 ) 76 24,067 Cost-recovery accounts: Water supply costs 8,679 (482 ) — — 8,197 — — — — — Pension (2,459 ) 161 — — (2,298 ) — — — — — Total cost-recovery accounts $ 6,220 (321 ) — — 5,899 $ — — — — — Total $ 27,925 (2,352 ) 2 — 25,575 $ 25,909 4,335 (6,253 ) 76 24,067 * As of March 31, 2018 and 2017 , the reserve balance for the 2017 WCMA was $1,022 and $0 , which has been netted from the balance above.

Regulatory Assets and Liabili26

Regulatory Assets and Liabilities (Tables)	3 Months Ended
	Mar. 31, 2018
Regulatory Assets and Liabilities Disclosure [Abstract]
Schedule of Regulatory Assets	Regulatory assets and liabilities are comprised of the following as of March 31, 2018 and December 31, 2017 : March 31, 2018 December 31, 2017 Regulatory assets: Postretirement pensions and other medical benefits $ 68,556 68,556 Balancing and memorandum accounts, net 25,575 27,925 Other, net 3,162 3,073 Total regulatory assets, net in Consolidated Balance Sheets $ 97,293 99,554 Regulatory liability: Income tax temporary differences, net $ 62,205 62,476 Total regulatory liability in Consolidated Balance Sheets $ 62,205 62,476

General - Additional Informatio

General - Additional Information (Details) - USD ($) $ in Thousands	Jun. 14, 2016	Mar. 31, 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
	Mar. 31, 2018	Mar. 31, 2017
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Revenue from contracts with customers	$ 75,869	$ 68,567
Alternative revenue programs, net - WCMA	(332)	2,276
Other balancing and memorandum accounts revenue, net	(1,836)	(3,361)
Rental income	1,341	1,563
Total revenues	75,042	$ 69,045
Reduction of revenue related to cost-recovery balancing accounts	$ 321

General - Earnings Per Share (D

General - Earnings Per Share (Details) - shares	3 Months Ended
	Mar. 31, 2018	Mar. 31, 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)	1,162	2,006

General - Depreciation (Details

General - Depreciation (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
General and Administrative Expense
Public Utility, Property, Plant and Equipment [Line Items]
Depreciation	$ 577	$ 527

Equity Plans (Details)

Equity Plans (Details) $ / shares in Units, $ in Thousands	Jan. 30, 2018$ / sharesshares	Jan. 02, 2018vesting_installment$ / sharesshares	Mar. 31, 2018USD ($)shares	Mar. 31, 2017USD ($)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation costs charged to income: | $			$ 487	$ 586
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: | $			$ 372	486
Recognition period for unrecognized compensation cost			1 year 6 months
Unrecognized compensation costs | $			$ 2,394
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
Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Remaining shares available for issuance under the Incentive Plan (shares) | shares			890,179
Shares issuable upon exercise of Incentive Plan awards (shares) | shares			191,547
Employee Stock Purchase Plan (ESPP)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation costs charged to income: | $			$ 115	100
Proceeds from ESPP | $			$ 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%
Plan expense | $			$ 53	$ 63
Unrecognized compensation costs | $			$ 107
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

Real Estate Investments (Detail

Real Estate Investments (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Dec. 31, 2017
Schedule of Investments [Line Items]
Land	$ 13,262	$ 13,262
Buildings and improvements	42,951	42,951
Subtotal	56,213	56,213
Less accumulated depreciation and amortization	11,431	11,132
Total	$ 44,782	$ 45,081
Minimum
Schedule of Investments [Line Items]
Estimated useful life	7 years
Maximum
Schedule of Investments [Line Items]
Estimated useful life	39 years

Defined Benefit Plan (Details)

Defined Benefit Plan (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018		Mar. 31, 2017	Dec. 31, 2017
Net Periodic Benefit Cost - Comprehensive Income Presentation [Abstract]
Pension non-service cost	$ 583		$ 871
Net periodic benefit cost	2,179		2,201
Components of Net Periodic Benefit Cost [Abstract]
Service cost	1,596		1,330
Interest cost	1,877		1,903
Other cost	1,133		1,038
Expected return on assets	(2,427)		(2,070)
Net periodic benefit cost	2,179		2,201
Plan Assets [Abstract]
Fair value of plan assets	137,981			$ 140,164
Employer Contributions [Abstract]
Capitalized pension non-service cost			128
Estimated employer contributions for the current fiscal year	7,450
Defined Contribution Plan, Employer Discretionary Contribution Amount	0
Quoted Prices in Active Markets for Identical Assets
Plan Assets [Abstract]
Fair value of plan assets	87,205			88,990
Significant Observable Inputs
Plan Assets [Abstract]
Fair value of plan assets	50,776			51,174
Significant Unobservable Inputs
Plan Assets [Abstract]
Fair value of plan assets	$ 0			0
Equity Securities [Member]
Plan Assets [Abstract]
Target plan asset allocations	55.00%
Fixed Income Securities
Plan Assets [Abstract]
Target plan asset allocations	45.00%
Cash and cash equivalents
Plan Assets [Abstract]
Fair value of plan assets	$ 5,928			8,207
Cash and cash equivalents | Quoted Prices in Active Markets for Identical Assets
Plan Assets [Abstract]
Fair value of plan assets	5,928			8,207
Cash and cash equivalents | Significant Observable Inputs
Plan Assets [Abstract]
Fair value of plan assets	0			0
Cash and cash equivalents | Significant Unobservable Inputs
Plan Assets [Abstract]
Fair value of plan assets	0			0
Actively Managed | All Cap Equity
Plan Assets [Abstract]
Fair value of plan assets	6,190	[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	6,151	[1]		6,376	[2]
Actively Managed | All Cap Equity | Significant Observable Inputs
Plan Assets [Abstract]
Fair value of plan assets	39	[1]		37	[2]
Actively Managed | All Cap Equity | Significant Unobservable Inputs
Plan Assets [Abstract]
Fair value of plan assets	0	[1]		0	[2]
Actively Managed | U.S. Large Cap Equity
Plan Assets [Abstract]
Fair value of plan assets	50,495	[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	50,495	[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	[2]
Actively Managed | U.S. Large Cap Equity | Significant Unobservable Inputs
Plan Assets [Abstract]
Fair value of plan assets	0	[1]		0	[2]
Actively Managed | U.S. Mid Cap Equity
Plan Assets [Abstract]
Fair value of plan assets	9,376	[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	9,376	[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	[2]
Actively Managed | U.S. Mid Cap Equity | Significant Unobservable Inputs
Plan Assets [Abstract]
Fair value of plan assets	0	[1]		0	[2]
Actively Managed | U.S. Small Cap Equity
Plan Assets [Abstract]
Fair value of plan assets	9,306	[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	9,306	[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	[2]
Actively Managed | U.S. Small Cap Equity | Significant Unobservable Inputs
Plan Assets [Abstract]
Fair value of plan assets	0	[1]		0	[2]
Actively Managed | Non-U.S. Large Cap Equity
Plan Assets [Abstract]
Fair value of plan assets	5,949	[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	5,949	[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	[2]
Actively Managed | Non-U.S. Large Cap Equity | Significant Unobservable Inputs
Plan Assets [Abstract]
Fair value of plan assets	0	[1]		0	[2]
Actively Managed | REIT
Plan Assets [Abstract]
Fair value of plan assets	5,864	[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	[2]
Actively Managed | REIT | Significant Observable Inputs
Plan Assets [Abstract]
Fair value of plan assets	5,864	[1]		6,143	[2]
Actively Managed | REIT | Significant Unobservable Inputs
Plan Assets [Abstract]
Fair value of plan assets	0	[1]		0	[2]
Fixed Income
Plan Assets [Abstract]
Fair value of plan assets	44,873	[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	[4]
Fixed Income | Significant Observable Inputs
Plan Assets [Abstract]
Fair value of plan assets	44,873	[3]		44,994	[4]
Fixed Income | Significant Unobservable Inputs
Plan Assets [Abstract]
Fair value of plan assets	0	[3]		$ 0	[4]
ASU 2017-07
Net Periodic Benefit Cost - Comprehensive Income Presentation [Abstract]
Administrative and general	895		745
Maintenance expense	278		237
Pension non-service cost	583		871
Net periodic benefit cost	2,179		2,201
Components of Net Periodic Benefit Cost [Abstract]
Other cost	423		348
Net periodic benefit cost	$ 2,179		$ 2,201
[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 Busi34

Segment and Non-Tariffed Business Reporting (Details) $ in Thousands		3 Months Ended
		Mar. 31, 2018USD ($)subsidiaryreportable_segment	Mar. 31, 2017USD ($)	Dec. 31, 2017USD ($)
Segment Reporting Information [Line Items]
Number of subsidiaries | subsidiary		4
Number of reportable business segments | reportable_segment		2
Operating revenue		$ 75,042	$ 69,045
Operating expense		67,711	57,341
Operating income (loss)		7,331	11,704
Net income (loss) before noncontrolling interest		1,285	3,671
Depreciation and amortization		13,583	12,119
Senior note, mortgage and other interest expense		6,052	6,057
Income tax expense (benefit) in net income		(580)	1,568
Assets		1,463,874	1,435,777	$ 1,458,001
Water Utility Services | Regulated
Segment Reporting Information [Line Items]
Operating revenue		72,353	66,218
Operating expense		61,701	54,750
Operating income (loss)		10,652	11,468
Net income (loss) before noncontrolling interest		4,795	3,949
Depreciation and amortization		13,201	11,660
Senior note, mortgage and other interest expense		5,508	5,425
Income tax expense (benefit) in net income		492	1,793
Assets		1,413,300	1,360,599
Water Utility Services | Non-tariffed
Segment Reporting Information [Line Items]
Operating revenue		1,348	1,264
Operating expense		888	831
Operating income (loss)		460	433
Net income (loss) before noncontrolling interest		331	172
Depreciation and amortization		83	136
Senior note, mortgage and other interest expense		0	0
Income tax expense (benefit) in net income		129	137
Assets		3,690	18,247
Real Estate Services | Non-tariffed
Segment Reporting Information [Line Items]
Operating revenue		1,341	1,563
Operating expense		849	948
Operating income (loss)		492	615
Net income (loss) before noncontrolling interest		356	360
Depreciation and amortization		299	323
Senior note, mortgage and other interest expense		0	65
Income tax expense (benefit) in net income		94	128
Assets		47,380	54,269
All Other | Non-tariffed
Segment Reporting Information [Line Items]
Operating revenue	[1]	0	0
Operating expense	[1]	4,273	812
Operating income (loss)	[1]	(4,273)	(812)
Net income (loss) before noncontrolling interest	[1]	(4,197)	(810)
Depreciation and amortization	[1]	0	0
Senior note, mortgage and other interest expense	[1]	544	567
Income tax expense (benefit) in net income	[1]	(1,295)	(490)
Assets	[1]	(496)	2,662
SJW Group | Regulated
Segment Reporting Information [Line Items]
Operating revenue		72,353	66,218
Operating expense		61,701	54,750
Operating income (loss)		10,652	11,468
Net income (loss) before noncontrolling interest		4,795	3,949
Depreciation and amortization		13,201	11,660
Senior note, mortgage and other interest expense		5,508	5,425
Income tax expense (benefit) in net income		492	1,793
Assets		1,413,300	1,360,599
SJW Group | Non-tariffed
Segment Reporting Information [Line Items]
Operating revenue		2,689	2,827
Operating expense		6,010	2,591
Operating income (loss)		(3,321)	236
Net income (loss) before noncontrolling interest		(3,510)	(278)
Depreciation and amortization		382	459
Senior note, mortgage and other interest expense		544	632
Income tax expense (benefit) in net income		(1,072)	(225)
Assets		$ 50,574	$ 75,178
[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
	Mar. 31, 2018	Mar. 31, 2017	Dec. 31, 2017
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term debt	$ 431,175		$ 431,092
Unrealized loss on California Water Service Group stock	667	$ 0
Significant Observable Inputs
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term debt, fair value	512,151		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	$ 3,067		$ 4,535

Regulatory Rate Filings (Detail

Regulatory Rate Filings (Details) - USD ($) $ in Thousands	Apr. 19, 2018	Mar. 22, 2018	Nov. 29, 2017	Nov. 15, 2017	Mar. 31, 2018	Nov. 28, 2017	Dec. 31, 2017	Jan. 04, 2018
Public Utilities, General Disclosures [Line Items]
Revenue increase amount				$ 15,670
Revenue increase, percentage				4.22%
Public Utilities, Approved Reimbursement Fee, Percentage			1.40%			1.44%
Public Utilities, Requested Equity Capital Structure, Percentage							8.09%
Public Utilities, Approved Equity Capital Structure, Percentage		7.64%
Public Utilities, Approved Equity Capital Structure, Decrease, Amount					$ 5,843
Public Utilities, Approved Equity Capital Structure, Decrease, Percent					1.57%
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
SJWTX, Inc. [Member]
Public Utilities, General Disclosures [Line Items]
Regulatory Liability, Current					$ 139
Subsequent Event [Member] | SJWTX, Inc. [Member]
Public Utilities, General Disclosures [Line Items]
Public Utilities, Requested Rate Increase (Decrease), Amended, Amount	$ (745)

Balancing and Memorandum Acco37

Balancing and Memorandum Account Recovery Procedures (Details) - USD ($) $ in Thousands		3 Months Ended
		Mar. 31, 2018	Mar. 31, 2017
Balancing and Memorandum Revenue Account [Roll Forward]
Beginning Balance		$ 21,705	$ 25,909
Regulatory Asset Increase (Decrease)		(2,031)	4,335
Refunds (Collections)		2	(6,253)
Surcharge Offset		0	76
Ending Balance		19,676	24,067
Balancing and Memorandum Cost Recovery Account [Roll Forward]
Beginning Balance		6,220	0
Regulatory Asset Increase (Decrease)		(321)	0
Refunds (Collections)		0	0
Surcharge Offset		0	0
Ending Balance		5,899	0
Balancing and Memorandum Account [Roll Forward]
Beginning Balance		27,925	25,909
Regulatory Asset Increase (Decrease)		(2,352)	4,335
Refunds (Collections)		2	(6,253)
Surcharge Offset		0	76
Ending Balance		25,575	24,067
Regulatory Balancing and Memorandum Accounts, Net Under-Collected		3,910
2014-2016 WCMA
Balancing and Memorandum Revenue Account [Roll Forward]
Beginning Balance		190	1,589
Regulatory Asset Increase (Decrease)		79	1,448
Refunds (Collections)		1	(1,232)
Surcharge Offset		0	(1,407)
Ending Balance		270	398
2017 WCMA
Balancing and Memorandum Revenue Account [Roll Forward]
Beginning Balance	[1]	6,489	0
Regulatory Asset Increase (Decrease)	[1]	296	2,060
Refunds (Collections)	[1]	0	0
Surcharge Offset	[1]	0	(2,060)
Ending Balance	[1]	6,785	0
2018 WCMA
Balancing and Memorandum Revenue Account [Roll Forward]
Beginning Balance		0	0
Regulatory Asset Increase (Decrease)		(708)	0
Refunds (Collections)		0	0
Surcharge Offset		0	0
Ending Balance		(708)	0
Balancing and Memorandum Account [Roll Forward]
Memorandum Account, Revenue Increase (Reduction)		(708)
2012 General Rate Case true-up
Balancing and Memorandum Revenue Account [Roll Forward]
Beginning Balance		11,319	20,682
Regulatory Asset Increase (Decrease)		0	0
Refunds (Collections)		1	(2,258)
Surcharge Offset		0	0
Ending Balance		11,320	18,424
2015 General Rate Case true-up
Balancing and Memorandum Revenue Account [Roll Forward]
Beginning Balance		115	5,528
Regulatory Asset Increase (Decrease)		0	0
Refunds (Collections)		0	(1,431)
Surcharge Offset		0	0
Ending Balance		115	4,097
Cost of capital
Balancing and Memorandum Revenue Account [Roll Forward]
Beginning Balance		(144)	(817)
Regulatory Asset Increase (Decrease)		(1,165)	0
Refunds (Collections)		0	358
Surcharge Offset		0	0
Ending Balance		(1,309)	(459)
Tax memorandum
Balancing and Memorandum Revenue Account [Roll Forward]
Beginning Balance		0	0
Regulatory Asset Increase (Decrease)		(933)	0
Refunds (Collections)		0	0
Surcharge Offset		0	0
Ending Balance		(933)	0
Drought surcharges
Balancing and Memorandum Revenue Account [Roll Forward]
Beginning Balance		0	(7,688)
Regulatory Asset Increase (Decrease)		0	0
Refunds (Collections)		0	(833)
Surcharge Offset		0	3,467
Ending Balance		0	(5,054)
Water supply costs
Balancing and Memorandum Revenue Account [Roll Forward]
Beginning Balance		0	5,190
Regulatory Asset Increase (Decrease)		0	197
Refunds (Collections)		0	297
Surcharge Offset		0	0
Ending Balance		0	5,684
Balancing and Memorandum Cost Recovery Account [Roll Forward]
Beginning Balance		8,679	0
Regulatory Asset Increase (Decrease)		(482)	0
Refunds (Collections)		0	0
Surcharge Offset		0	0
Ending Balance		8,197	0
Pension
Balancing and Memorandum Revenue Account [Roll Forward]
Beginning Balance		0	(2,009)
Regulatory Asset Increase (Decrease)		0	173
Refunds (Collections)		0	(703)
Surcharge Offset		0	0
Ending Balance		0	(2,539)
Balancing and Memorandum Cost Recovery Account [Roll Forward]
Beginning Balance		(2,459)	0
Regulatory Asset Increase (Decrease)		161	0
Refunds (Collections)		0	0
Surcharge Offset		0	0
Ending Balance		(2,298)	0
All others
Balancing and Memorandum Revenue Account [Roll Forward]
Beginning Balance		3,736	3,434
Regulatory Asset Increase (Decrease)		400	457
Refunds (Collections)		0	(451)
Surcharge Offset		0	76
Ending Balance		4,136	3,516
2017 WCMA Reserve Recorded [Member]
Balancing and Memorandum Account [Roll Forward]
Memorandum Account, Revenue Increase (Reduction)		$ 1,022	$ 0
[1]	As of March 31, 2018 and 2017, the reserve balance for the 2017 WCMA was $1,022 and $0, which has been netted from the balance above.

Regulatory Assets and Liabili38

Regulatory Assets and Liabilities (Details) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Regulatory Assets [Line Items]
Net Regulatory Assets	$ 97,293	$ 99,554
Total regulatory liability in Consolidated Balance Sheets	62,205	62,476
Deferred Income Tax Charge [Member]
Regulatory Assets [Line Items]
Regulatory Liabilities	62,205	62,476
Postretirement pensions and other medical benefits
Regulatory Assets [Line Items]
Regulatory assets:	68,556	68,556
Balancing and memorandum accounts, net
Regulatory Assets [Line Items]
Regulatory assets:	25,575	27,925
Other, net
Regulatory Assets [Line Items]
Regulatory assets:	$ 3,162	$ 3,073

California Water Service Grou39

California Water Service Group Stock (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 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)	(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

SJW Group and Connecticut Water

SJW Group and Connecticut Water Service Merger Agreement (Details) - $ / shares	Mar. 14, 2018	Mar. 31, 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