California Water Service (CWT) 10-Q 6 Nov 13 2013 Q3 Quarterly report Financial data

Document_and_Entity_Informatio

Document and Entity Information	9 Months Ended
	Sep. 30, 2013	Oct. 31, 2013
Document and Entity Information	'	'
Entity Registrant Name	'CALIFORNIA WATER SERVICE GROUP	'
Entity Central Index Key	'0001035201	'
Document Type	'10-Q	'
Document Period End Date	30-Sep-13	'
Amendment Flag	'false	'
Current Fiscal Year End Date	'--12-31	'
Entity Current Reporting Status	'Yes	'
Entity Filer Category	'Large Accelerated Filer	'
Entity Common Stock, Shares Outstanding	'	47,739,024
Document Fiscal Year Focus	'2013	'
Document Fiscal Period Focus	'Q3	'

CONDENSED_CONSOLIDATED_BALANCE

CONDENSED CONSOLIDATED BALANCE SHEETS (USD $)	Sep. 30, 2013	Dec. 31, 2012
In Thousands, unless otherwise specified
Utility plant:	'	'
Utility plant	$2,190,573	$2,096,363
Less accumulated depreciation and amortization	-685,351	-639,307
Net utility plant	1,505,222	1,457,056
Current assets:	'	'
Cash and cash equivalents	48,847	38,790
Receivables: net of allowance for doubtful accounts of $815 as of September 30, 2013 and $714 as of December 31, 2012	'	'
Customers	42,979	29,958
Regulatory balancing accounts	27,047	34,020
Other	9,802	11,943
Unbilled revenue	25,815	15,394
Materials and supplies at weighted average cost	5,689	5,874
Taxes, prepaid expenses and other assets	10,373	10,585
Total current assets	170,552	146,564
Other assets:	'	'
Regulatory assets	354,879	344,419
Goodwill	2,615	2,615
Other assets	50,165	45,270
Total other assets	407,659	392,304
Total assets	2,083,433	1,995,924
Capitalization:	'	'
Common stock, $.01 par value; 68,000,000 shares authorized, 47,739,024 and 41,908,218 outstanding in 2013 and 2012, respectively	477	419
Additional paid-in capital	327,890	221,013
Retained earnings	271,887	252,280
Total common stockholders' equity	600,254	473,712
Long-term debt, less current maturities	430,227	434,467
Total capitalization	1,030,481	908,179
Current liabilities:	'	'
Current maturities of long-term debt	48,013	46,783
Short-term borrowings	11,515	89,475
Accounts payable	60,414	47,199
Regulatory balancing accounts	1,699	5,018
Accrued interest	10,656	4,705
Accrued expenses and other liabilities	64,716	49,887
Total current liabilities	197,013	243,067
Unamortized investment tax credits	2,180	2,180
Deferred income taxes, net	168,091	158,846
Pension and postretirement benefits other than pensions	247,335	244,901
Regulatory and other liabilities	91,185	92,593
Advances for construction	184,879	187,584
Contributions in aid of construction	162,269	158,574
Commitments and contingencies	'	'
Total capitalization and liabilities	$2,083,433	$1,995,924

CONDENSED_CONSOLIDATED_BALANCE1

CONDENSED CONSOLIDATED BALANCE SHEETS (Parenthetical) (USD $)	Sep. 30, 2013	Dec. 31, 2012
In Thousands, except Share data, unless otherwise specified
CONDENSED CONSOLIDATED BALANCE SHEETS	'	'
Receivables: allowance for doubtful accounts (in dollars)	$815	$714
Common stock, par value (in dollars per share)	$0.01	$0.01
Common stock, shares authorized	68,000,000	68,000,000
Common stock, shares outstanding	47,739,024	41,908,218

CONDENSED_CONSOLIDATED_STATEME

CONDENSED CONSOLIDATED STATEMENTS OF INCOME (USD $)	3 Months Ended		9 Months Ended
In Thousands, except Per Share data, unless otherwise specified	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
CONDENSED CONSOLIDATED STATEMENTS OF INCOME	'	'	'	'
Operating revenue	$184,404	$178,135	$450,403	$438,436
Operations:	'	'	'	'
Water production costs	70,614	66,489	171,956	158,119
Administrative and general	24,670	23,925	73,106	69,110
Other operations	17,657	17,658	50,332	59,213
Maintenance	4,575	4,377	12,896	14,742
Depreciation and amortization	14,505	13,720	43,625	41,383
Income taxes	11,165	10,387	19,567	19,477
Property and other taxes	5,414	5,218	16,564	13,802
Total operating expenses	148,600	141,774	388,046	375,846
Net operating income	35,804	36,361	62,357	62,590
Other income and expenses:	'	'	'	'
Non-regulated revenue	3,649	3,756	10,386	11,943
Non-regulated expenses, net	-2,825	-2,697	-8,482	-8,491
Income tax (expense) on other income and expenses	-330	-422	-765	-1,383
Net other income	494	637	1,139	2,069
Interest expense:	'	'	'	'
Interest expense	7,687	8,024	23,527	23,484
Less: capitalized interest	-540	-798	-1,619	-2,647
Net interest expense	7,147	7,226	21,908	20,837
Net income	$29,151	$29,772	$41,588	$43,822
Earnings per share	'	'	'	'
Basic (in dollars per share)	$0.61	$0.71	$0.91	$1.05
Diluted (in dollars per share)	$0.61	$0.71	$0.90	$1.05
Weighted average shares outstanding	'	'	'	'
Basic (in shares)	47,737	41,905	45,927	41,886
Diluted (in shares)	47,770	41,905	45,957	41,886
Dividends declared per share of common stock (in dollars per share)	$0.16	$0.16	$0.48	$0.47

CONDENSED_CONSOLIDATED_STATEME1

CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (USD $)	9 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2013	Sep. 30, 2012
Operating activities	'	'
Net income	$41,588	$43,822
Adjustments to reconcile net income to net cash provided by operating activities:	'	'
Depreciation and amortization	45,067	42,722
Change in value of life insurance contracts	-1,147	-2,244
Other changes in noncurrent assets and liabilities	13,501	28,411
Changes in operating assets and liabilities:	'	'
Receivables	-24,636	-34,462
Accounts payable	7,719	13,066
Other current assets	-751	-2,491
Other current liabilities	20,558	10,581
Net cash provided by operating activities	101,899	99,405
Investing activities:	'	'
Utility plant expenditures	-94,782	-99,600
Purchase of life insurance	-3,204	-3,199
Restricted cash decrease	1,148	1,553
Net cash (used in) investing activities	-96,838	-101,246
Financing activities:	'	'
Short-term borrowings	35,315	65,565
Repayment of short-term borrowing	-113,275	-52,030
Proceeds from long-term debt	48	123
Repayment of long-term debt	-3,058	-2,123
Advances and contributions in aid of construction	7,577	5,491
Refunds of advances for construction	-5,230	-5,632
Issuance of common stock	110,688	'
Common stock issuance cost	-5,088	'
Dividends paid	-21,981	-19,785
Net cash provided by (used in) financing activities	4,996	-8,391
Change in cash and cash equivalents	10,057	-10,232
Cash and cash equivalents at beginning of period	38,790	27,203
Cash and cash equivalents at end of period	48,847	16,971
Supplemental information	'	'
Cash paid for interest (net of amounts capitalized)	15,141	13,721
Refund for income taxes	'	-3,498
Supplemental disclosure of non-cash activities:	'	'
Accrued payables for investments in utility plant	11,739	9,654
Utility plant contribution by developers	$10,196	$11,868

Organization_and_Operations_an

Organization and Operations and Basis of Presentation	9 Months Ended
	Sep. 30, 2013
Organization and Operations and Basis of Presentation	'
Organization and Operations and Basis of Presentation	'
	Note 1. Organization and Operations and Basis of Presentation
	California Water Service Group (the Company) is a holding company that provides water utility and other related services in California, Washington, New Mexico and Hawaii through its 100% owned subsidiaries. California Water Service Company (Cal Water), Washington Water Service Company (Washington Water), New Mexico Water Service Company (New Mexico Water), and Hawaii Water Service Company, Inc. (Hawaii Water) provide regulated utility services under the rules and regulations of their respective state’s regulatory commissions (jointly referred to herein as the Commissions). CWS Utility Services and HWS Utility Services LLC provide non-regulated water utility and utility-related services.
	The Company operates in one reportable segment, providing water and related utility services.
	Basis of Presentation
	The unaudited interim financial information has been prepared in accordance with accounting principles generally accepted in the United States of America (GAAP) for interim financial information and in accordance with the instructions to Form 10-Q and Rule 10-01 of Regulation S-X promulgated by the Securities and Exchange Commission (SEC) and therefore do not contain all of the information and footnotes required by GAAP and the SEC for annual financial statements. The condensed consolidated financial statements should be read in conjunction with the Company’s consolidated financial statements for the year ended December 31, 2012, included in its annual report on Form 10-K as filed with the SEC on February 28, 2013.
	The preparation of the Company’s condensed consolidated financial statements in accordance with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the balance sheet dates and the reported amounts of revenues and expenses for the periods presented. These include, but are not limited to, estimates and assumptions used in determining the Company’s regulatory asset and liability balances based upon probability assessments of regulatory recovery, revenues earned but not yet billed, asset retirement obligations, allowance for doubtful accounts, pension and other employee benefit plan liabilities, and income tax-related assets and liabilities.  Actual results could differ from these estimates.
	In the opinion of management, the accompanying condensed consolidated financial statements reflect all adjustments, consisting of normal recurring accruals that are necessary to provide a fair presentation of the results for the periods covered. The results for interim periods are not necessarily indicative of the results for any future period.
	Due to the seasonal nature of the water business, the results for interim periods are not indicative of the results for a 12-month period. Revenue and income are generally higher in the warm, dry summer months when water usage and sales are greater. Revenue and income are lower in the winter months when cooler temperatures and rainfall curtail water usage and sales.
	The Company evaluated its operations through the time these financials were issued and determined there were no subsequent events requiring adjustments or disclosures as of the time these financial statements were issued.

Summary_of_Significant_Account

Summary of Significant Accounting Policies	9 Months Ended
	Sep. 30, 2013
Summary of Significant Accounting Policies	'
Summary of Significant Accounting Policies	'
	Note 2. Summary of Significant Accounting Policies
	Revenue
	Revenue generally includes monthly cycle customer billings for regulated water and wastewater services at rates authorized by regulatory commissions (plus an estimate for water used between the customer’s last meter reading and the end of the accounting period) and billings to certain non-regulated customers at rates authorized by contract with government agencies.
	The Company’s regulated water and waste water revenue requirements are authorized by the Commissions in the states in which it operates. The revenue requirements are intended to provide the Company a reasonable opportunity to recover its operating costs and earn a return on investments.
	For metered customers, Cal Water recognizes revenue from rates which are designed and authorized by the California Public Utilities Commission (CPUC). Under the Water Revenue Adjustment Mechanism (WRAM), Cal Water records the adopted level of volumetric revenues, which would include recovery of cost of service and a return on investments, as established by the CPUC for metered accounts (adopted volumetric revenues). In addition to volumetric-based revenues, the revenue requirements approved by the CPUC include service charges, flat rate charges, and other items not subject to the WRAM. The adopted volumetric revenue considers the seasonality of consumption of water based upon historical averages. The variance between adopted volumetric revenues and actual billed volumetric revenues for metered accounts is recorded as a component of revenue with an offsetting entry to a regulatory asset or liability balancing account (tracked individually for each Cal Water district) subject to certain criteria under the accounting for regulated operations being met. The variance amount may be positive or negative and represents amounts that will be billed or refunded to customers in the future.
	Cost-recovery rates are designed to permit full recovery of certain costs allowed to be recovered by the Commissions. Cost-recovery rates such as the Modified Cost Balancing Account (MCBA) provides for recovery of adopted expense levels for purchased water, purchased power and pump taxes, as established by the CPUC. In addition, cost-recovery rates include recovery of cost related to water conservation programs and certain other operation expenses adopted by the CPUC. Variances (which include the effects of changes in both rate and volume for the MCBA) between adopted and actual costs are recorded as a component of revenue, as the amount of such variances will be recovered from or refunded to our customers at a later date. There is no markup for return or profit for cost-recovery expenses and they are generally recognized when expenses are incurred.
	The balances in the WRAM and MCBA assets and liabilities accounts will fluctuate on a monthly basis depending upon the variance between adopted and actual results. The recovery or refund of the WRAM is netted against the MCBA over- or under-recovery for the corresponding district and is interest bearing at the current 90 day commercial paper rate. At the end of any calendar year, Cal Water files with the CPUC to refund or collect the balance in the accounts. Most undercollected net WRAM and MCBA receivable balances are collected over 12 and 18 months. Cal Water defers net WRAM and MCBA operating revenues and associated costs whenever the net receivable balances are estimated to be collected more than 24 months after the respective reporting periods in which it was recognized. The deferred net WRAM and MCBA revenues and associated costs were determined using forecasts of rate payer consumption trends in future reporting periods and the timing of when the CPUC will authorize Cal Water’s filings to recover the undercollected balances. Deferred net WRAM and MCBA revenues and associated costs will be recognized as revenues and costs in future periods when collection is within twenty-four months of the respective reporting period.
	The change to deferred net WRAM and MCBA balances during the nine months ended September 30, 2013 was:
		Operating			Operating			Income Before
		Revenues			Costs			Income Taxes
	Net WRAM and MCBA deferral as of December 31, 2012	$	882		$	719		$	163
	Less: reversal of prior year deferral during the nine months ended September 30, 2013	(1,911		)	(1,603		)	(308		)
	Add: net WRAM and MCBA deferral during the nine months ended September 30, 2013	2,764			2,375			389
	Net amount during the nine months ended September 30, 2013	853			772			81
	Net WRAM and MCBA deferral as of September 30, 2013	$	1,735		$	1,491		$	244
	The change to deferred net WRAM and MCBA balances during the nine months ended September 30, 2012 was:
		Operating			Operating			Income Before
		Revenues			Costs			Income Taxes
	Net WRAM and MCBA deferral as of December 31, 2011	$	12,864		$	10,492		$	2,372
	Less: reversal of prior year deferral during the nine months ended September 30, 2012	(12,295		)	(10,027		)	(2,268		)
	Add: net WRAM and MCBA deferral during the nine months ended September 30, 2012	939			766			173
	Net amount during the nine months ended September 30, 2012	(11,356		)	(9,261		)	(2,095		)
	Net WRAM and MCBA deferral as of September 30, 2012	$	1,508		$	1,231		$	277
	The net WRAM and MCBA under- or overcollected balances are:
		September 30,			December 31,
		2013			2012
	Net short-term regulatory balancing accounts (receivable)	$	27,047		$	34,020
	Net long-term regulatory assets (receivable)	21,925			12,051
	Total regulatory assets	$	48,972		$	46,071
	Net short-term regulatory balancing accounts (liability)	$	174		$	371
	Net long-term regulatory liability	108			119
	Total regulatory liabilities	$	282		$	490
	Flat rate customers are billed in advance at the beginning of the service period. The revenue is prorated so that the portion of revenue applicable to the current period is included in that period’s revenue, with the balance recorded as unearned revenue on the balance sheet and recognized as revenue when earned in the subsequent accounting period. Unearned revenue liability was $1.5 million and $1.7 million as of September 30, 2013 and December 31, 2012, respectively. This liability is included in “accrued expenses and other liabilities” on the condensed consolidated balance sheets.
	Cash and Cash Equivalents
	Cash equivalents include highly liquid investments with maturities of three months or less.  Cash and cash equivalents was $48.8 million and $38.8 million as of September 30, 2013 and December 31, 2012, respectively.  Restricted cash is included in “taxes, prepaid expenses and other assets” and was $1.1 million and $2.3 million as of September 30, 2013 and December 31, 2012, respectively.
	Adoption of New Accounting Standards
	On February 1, 2013, the Financial Accounting Standards Board issued an accounting standards update (ASU) for the recognition, measurement, and disclosure of obligations resulting from joint and several liability arrangements.  The ASU would impact the Company’s recognition, measurement, and disclosure requirements for guarantees of third party debt.  The ASU effective date for the Company’s interim and annual reporting is January 1, 2014.  The Company has completed a review of all contracts and has not identified any joint and several liability arrangements.

Stockbased_Compensation

Stock-based Compensation	9 Months Ended
	Sep. 30, 2013
Stock-based Compensation	'
Stock-based Compensation	'
	Note 3. Stock-based Compensation
	Equity Incentive Plan
	The Company’s equity incentive plan was approved by stockholders on April 27, 2005.  The Company is authorized to issue awards up to 2,000,000 shares of common stock.
	During the nine months ended September 30, 2013 and 2012, the Company granted annual Restricted Stock Awards (RSAs) of 72,891 and 98,422 shares, respectively, of common stock to officers and directors of the Company and no RSAs were cancelled. Employee RSAs granted in 2013 vest over 36 months and RSAs granted in 2012 vest over 48 months.  Director RSAs generally vest at the end of 12 months. During the first nine months of 2013 and 2012, the shares granted were valued at $20.66 and $17.96 per share, respectively, based upon the fair market value of the Company’s common stock on the date of grant.
	On March 1, 2013, the Company granted performance-based Restricted Stock Unit Awards (RSUs) of 50,267 shares of common stock to officers.  Each award reflects a target number of shares that may be issued to the award recipient.  The awards may be earned upon the completion of the three-year performance period ending February 28, 2016.  Whether RSUs are earned at the end of the performance period will be determined based on the achievement of certain performance objectives set by the Board of Director Compensation Committee in connection with the issuance of the RSUs.  The performance objectives are based on the Company’s business plan covering the performance period.  The performance objectives include achieving the budgeted return on equity, budgeted investment in utility plant, customer service standards, and water quality standards.  Depending on the results achieved during the three-year performance period, the actual number of shares that a grant recipient receives at the end of the performance period may range from 0% to 200% of the target shares granted, provided that the grantee is continuously employed by the Company through the vesting date.  If prior to the vesting date employment is terminated by reason of death, disability or normal retirement, then a pro rata portion of this award will vest.  RSUs are not included in diluted shares for financial reporting until earned.  The RSUs are recognized as expense ratably over the three year performance period using a fair market value of $20.62 per share and an estimate of RSUs earned during the performance period.
	The Company has recorded compensation costs for the RSAs and RSUs which are included in operating expense in the amount of $1.3 million and $1.1 million for the nine months ended September 30, 2013 and September 30, 2012, respectively.  The Company has recorded compensation costs for the RSAs and RSUs in operating expense in the amount of $0.5 million and $0.3 million for the three months ended September 30, 2013 and September 30, 2012, respectively.

Equity

Equity	9 Months Ended
	Sep. 30, 2013
Equity	'
Equity	'
	Note 4. Equity
	The Company’s changes in equity for the nine months ended September 30, 2013 were as follows:
		Total Stockholders’ Equity
	Balance at December 31, 2012	$	473,712
	Common stock issued, net	105,600
	Share-based compensation expense	1,335
	Common stock dividends declared	(21,981		)
	Net income	41,588
	Balance at September 30, 2013	$	600,254
	On March 26, 2013, the Company sold 5,750,000 shares of its common stock in an underwritten public offering for cash proceeds of $105.6 million, net of $5.1 million underwriting discounts and commissions and offering expenses. The net proceeds from the sale of common stock were added to our general funds to be used for general corporate purposes.  In April 2013, the Company used a portion of the net proceeds from the offering to repay outstanding borrowings on the Company and Cal Water lines of credit of $68.3 million and $25.0 million, respectively.

Earnings_Per_Share_Calculation

Earnings Per Share Calculations	9 Months Ended
	Sep. 30, 2013
Earnings Per Share Calculations	'
Earnings Per Share Calculations	'
	Note 5. Earnings Per Share Calculations
	The computations of basic and diluted earnings per share are noted below. Basic earnings per share are computed by dividing net income available to common stockholders by the weighted average number of common shares outstanding during the period. Diluted earnings per share reflect the potential dilution that could occur if securities or other contracts were exercised or converted into common stock. RSAs are included in the common shares outstanding because the shares have all the same voting and dividend rights as issued and unrestricted common stock.
	A total of 283,856 shares of Stock Appreciation Rights were vested and outstanding and all were dilutive as of September 30, 2013 and anti-dilutive as of September 30, 2012 as shown in the tables below.
		Three months Ended September 30
		2013		2012
	Net income available to common stockholders	$	29,151	$	29,772
	Weighted average common shares, basic	47,737		41,905
	Dilutive common stock appreciation rights (treasury method)	33		—
	Shares used for dilutive computation	47,770		41,905
	Net income per share - basic	$	0.61	$	0.71
	Net income per share - diluted	$	0.61	$	0.71
		Nine months Ended September 30
		2013		2012
	Net income available to common stockholders	$	41,588	$	43,822
	Weighted average common shares, basic	45,927		41,886
	Dilutive common stock appreciation rights (treasury method)	30		—
	Shares used for dilutive computation	45,957		41,886
	Net income per share - basic	$	0.91	$	1.05
	Net income per share - diluted	$	0.9	$	1.05

Pension_Plan_and_Other_Postret

Pension Plan and Other Postretirement Benefits	9 Months Ended
	Sep. 30, 2013
Pension Plan and Other Postretirement Benefits	'
Pension Plan and Other Postretirement Benefits	'
	Note 6. Pension Plan and Other Postretirement Benefits
	The Company provides a qualified, defined-benefit, non-contributory pension plan for substantially all employees. The Company makes annual contributions to fund the amounts accrued for the qualified pension plan. The Company also maintains an unfunded, non-qualified, supplemental executive retirement plan. The costs of the plans are charged to expense or are capitalized in utility plant as appropriate.
	The Company offers medical, dental, vision, and life insurance benefits for retirees and their spouses and dependents. Participants are required to pay a premium, which offsets a portion of the cost.
	Cash payments by the Company related to pension plans and other postretirement benefit plans were $28.1 million for the nine months ended September 30, 2013 and $25.5 million for the nine months ended September 30, 2012. The 2013 estimated cash contribution to the pension plans is $31.1 million and to the other postretirement benefit plans is $7.2 million.
	The following table lists components of net periodic benefit costs for the pension plans and other postretirement benefits. The data listed under “pension plan” includes the qualified pension plan and the non-qualified supplemental executive retirement plan. The data listed under “other benefits” is for all other postretirement benefits.
		Three months Ended September 30
		Pension Plan						Other Benefits
		2013			2012			2013			2012
	Service cost	$	4,019		$	3,863		$	1,636		$	1,374
	Interest cost	4,140			3,822			1,121			986
	Expected return on plan assets	(3,559		)	(2,890		)	(600		)	(458		)
	Recognized net initial APBO (1)	N/A			N/A			3			69
	Amortization of prior service cost	1,542			1,571			21			29
	Recognized net actuarial loss	2,404			2,000			961			793
	Net periodic benefit cost	$	8,546		$	8,366		$	3,142		$	2,793
		Nine months Ended September 30
		Pension Plan						Other Benefits
		2013			2012			2013			2012
	Service cost	$	13,335		$	11,588		$	5,025		$	4,121
	Interest cost	12,266			11,465			3,339			2,958
	Expected return on plan assets	(10,689		)	(8,669		)	(1,796		)	(1,374		)
	Recognized net initial APBO (1)	N/A			N/A			7			207
	Amortization of prior service cost	4,624			4,712			61			87
	Recognized net actuarial loss	6,852			6,001			2,794			2,379
	Net periodic benefit cost	$	26,388		$	25,097		$	9,430		$	8,378
	(1)      APBO - Accumulated postretirement benefit obligation

Shortterm_and_Longterm_Borrowi

Short-term and Long-term Borrowings	9 Months Ended
	Sep. 30, 2013
Short-term and Long-term Borrowings	'
Short-term and Long-term Borrowings	'
	Note 7. Short-term and Long-term Borrowings
	On June 29, 2011, the Company and Cal Water entered into Syndicated Credit Facilities, which provide for unsecured revolving credit facilities of up to an initial aggregate amount of $400 million.  The Syndicated Credit Facilities amend, expand, and replace the Company’s and its subsidiaries’ existing credit facilities originally entered into on October 27, 2009.  The new credit facilities extended the terms until June 29, 2016, increased the Company’s and Cal Water’s unsecured revolving lines of credit, and lowered interest rates and fees.  The Company and subsidiaries which it designates may borrow up to $100 million under the Company’s revolving credit facility. Cal Water may borrow up to $300 million under its revolving credit facility; however, all borrowings need to be repaid within 12-months unless otherwise authorized by the CPUC.  The proceeds from the revolving credit facilities may be used for working capital purposes, including the short-term financing of capital projects.  The base loan rate may vary from LIBOR plus 72.5 basis points to LIBOR plus 95 basis points, depending on the Company’s total capitalization ratio.  Likewise, the unused commitment fee may vary from 8 basis points to 12.5 basis points based on the same ratio.
	Both short-term unsecured credit agreements contain affirmative and negative covenants and events of default customary for credit facilities of this type including, among other things, limitations and prohibitions relating to additional indebtedness, liens, mergers, and asset sales. Also, these unsecured credit agreements contain financial covenants governing the Company and its subsidiaries’ consolidated total capitalization ratio and interest coverage ratio. As of September 30, 2013, the Company and Cal Water have met all borrowing covenants for both credit agreements.
	As of September 30, 2013 and December 31, 2012, the outstanding borrowings on the Company lines of credit were $11.5 million and $64.5 million, respectively, and the outstanding borrowings on the Cal Water lines of credit were zero million and $25.0 million, respectively.  For the nine months ended September 30, 2013, the average borrowing rate was 2.2% compared to 1.7% for the same period last year.

Income_Taxes

Income Taxes	9 Months Ended
	Sep. 30, 2013
Income Taxes	'
Income Taxes	'
	Note 8. Income Taxes
	The Company accounts for income taxes using the asset and liability method. Deferred tax assets and liabilities are recognized for the future tax consequences attributable to differences between the financial statement carrying amounts of existing assets and liabilities and their respective tax bases. Measurement of the deferred tax assets and liabilities is at enacted tax rates expected to apply to taxable income in the years in which those temporary differences are expected to be recovered or settled. The effect on deferred tax assets and liabilities of a change in tax rates is recognized in the period that includes the enactment date.
	The Company anticipates that future rate actions by the regulatory commissions will reflect revenue requirements for the tax effects of temporary differences recognized, which have previously been passed through to customers. The regulatory commissions have granted us rate increases to reflect the normalization of the tax benefits of the federal accelerated methods and available Investment Tax Credits (ITCs) for all assets placed in service after 1980. ITCs are deferred and amortized over the lives of the related properties for book purposes.
	During the third quarter of 2013, the Company recorded $4.4 million of State of California enterprise zone (EZ) credits for sales and use taxes and hiring incentives for the period from 2008 to 2013 based on an analysis of all district operations.    The Company filed amended state income tax returns for tax years 2008, 2009, 2010 and 2011.  The State of California EZ credits were included on the Company’s 2012 state income tax returns filed during the fourth quarter of 2013. Unused State of California EZ credits, if any, can be carried-forward ten years.  The Company estimates the carried-forward portion of its State of California EZ credits at $2.3 million.  The Company’s analysis of State of California EZ credits as of September 30, 2013 resulted in the recognition of a  $0.6 million liability for unrecognized tax benefits.
	During 2012, the Company filed an application for a change in accounting method (section 481 adjustment) with the Internal Revenue Service (IRS) to implement the repairs and maintenance deduction.   These tax regulations allowed the Company to deduct a significant amount of water main costs previously capitalized for book and tax purposes.  The 2012 repairs and maintenance deductions resulted in a federal net operating loss (NOL) of $38.8 million and state NOL of $58.4 million.  On September 19, 2013, the U. S. Department of the Treasury and IRS issued final and re-proposed tangible property regulations with an effective date of January 1, 2014.  An application for a change in accounting method can be filed to adopt the new tax regulations before January 1, 2014.  The final and re-proposed tangible property regulations will provide the Company with additional repairs and maintenance deductions for equipment such as fire hydrants, pumps, meters, and carbon filters.  The Company does not expect any material changes to the previous filed method change as a result of the early adoption.  The Company estimated 2013 equipment repairs and maintenance deductions of $5.0 million and recorded the estimate as of September 30, 2013.  The 2012 federal and state income tax NOLs were carried-forward to reduce 2013 income tax payments. The NOL carry-forward amounts are more likely than not to be recovered and therefore require no valuation allowance.  The NOL carry-forward does not begin to expire until 2033.
	The American Taxpayer Relief Act of 2012 provided the Company with additional 50% first-year bonus depreciation for assets placed in service from December 31, 2012 to December 31, 2013. The federal income tax bonus deduction was estimated at $10.0 million in 2013 and was $14.5 million in 2012.
	On October 24, 2013, the IRS completed an  audit of the Company’s 2010 and 2011 federal income tax returns with no changes to our previously reported taxes.

Regulatory_Assets_and_Liabilit

Regulatory Assets and Liabilities	9 Months Ended
	Sep. 30, 2013
Regulatory Assets and Liabilities	'
Regulatory Assets and Liabilities	'
	Note 9. Regulatory Assets and Liabilities
	During 2011, the CPUC issued a decision regarding the $34.2 million of litigation proceeds previously received by Cal Water during 2008 which is being used to replace infrastructure damaged by the gasoline additive Methyl tert-butyl ether (MTBE). The decision requires use of these proceeds for costs incurred as a result of MTBE contamination with any related benefits to be provided to Cal Water customers. Such usage includes transfer of the amount to contributions in aid of construction (CIAC) for remediation or replacement project costs once complete. Usage of the proceeds is reported to the CPUC through an Advice Letter or General Rate Case filing. As of December 31, 2012, $22.4 million of the proceeds was recorded as CIAC.  Cal Water used $0.8 million of the net proceeds to replace damaged infrastructure during the third quarter of 2013.  The remaining balance of $9.8 million at September 30, 2013 is included in regulatory and other liabilities.
	During 2011, Cal Water added balancing accounts for its pension plans and conservation program. Both balancing account effective dates were January 1, 2011. The pension plans balancing account is a two-way balancing account that tracks the differences between actual expenses and adopted rate recovery which will result in either a regulatory asset or liability. The conservation program is a one-way balancing account that tracks the differences between actual expenses and adopted rate recovery which may result in a regulatory liability if actual conservation expenses are less than adopted over the three year period ending December 31, 2013. As of September 30, 2013 and December 31, 2012, the pension balancing account was a regulatory asset of $2.3 million and $2.4 million, respectively.  The conservation balancing account was a regulatory liability of $7.7 million and $6.5 million as of September 30, 2013 and December 31, 2012, respectively.

Commitment_and_Contingencies

Commitment and Contingencies	9 Months Ended
	Sep. 30, 2013
Commitment and Contingencies	'
Commitment and Contingencies	'
	Note 10. Commitment and Contingencies
	Commitments
	The Company has significant commitments to lease certain office spaces and water systems and to purchase water from water wholesalers. These commitments are described in Form 10-K for the year ended December 31, 2012.  As of September 30, 2013, there were no significant changes from December 31, 2012.
	Contingencies
	Groundwater Contamination
	The Company has undertaken litigation against third parties to recover past and future costs related to ground water contamination in our service areas. The cost of litigation is expensed as incurred and any settlement is first offset against such costs. The Company records gain contingencies as a regulatory liability when the net litigation proceeds are received.  The Commission’s general policy requires all proceeds from contamination litigation to be used first to pay transactional expenses, then to make ratepayers whole for water treatment costs to comply with the Commission’s water quality standards. The Commission allows for a risk-based consideration of contamination proceeds which exceed the costs of the remediation described above and may result in some sharing of proceeds with the shareholder, determined on a case by case basis. The Commission has authorized various memorandum accounts that allow the Company to track significant litigation costs to request recovery of these costs in future filings and uses of proceeds to comply with Commission’s general policy.
	Other Legal Matters
	From time to time, the Company is involved in various disputes and litigation matters that arise in the ordinary course of business. The status of each significant matter is reviewed and assessed for potential financial exposure. If the potential loss from any claim or legal proceeding is considered probable and the amount of the range of loss can be estimated, a liability is accrued for the estimated loss in accordance with the accounting standards for contingencies. Legal proceedings are subject to uncertainties, and the outcomes are difficult to predict. Because of such uncertainties, accruals are based on the best information available at the time. While the outcome of these disputes and litigation matters cannot be predicted with any certainty, management does not believe when taking into account existing reserves the ultimate resolution of these matters will materially affect the Company’s financial position, results of operations, or cash flows.  The Company has recognized a liability of $1.1 million for all known legal matters as of September 30, 2013 and December 31, 2012.  The cost of litigation is expensed as incurred and any settlement is first offset against such costs.  Any settlement in excess of the cost to litigate is accounted for on a case by case basis, dependant on the nature of the settlement.

Fair_Value_of_Financial_Assets

Fair Value of Financial Assets and Liabilities	9 Months Ended
	Sep. 30, 2013
Fair Value of Financial Assets and Liabilities	'
Fair Value of Financial Assets and Liabilities	'
	Note 11. Fair Value of Financial Assets and Liabilities
	The accounting guidance for fair value measurements and disclosures provides a single definition of fair value and requires certain disclosures about assets and liabilities measured at fair value. A hierarchal framework for disclosing the observability of the inputs utilized in measuring assets and liabilities at fair value is established by this guidance. The three levels in the hierarchy are as follows:
	Level 1 -	Quoted prices are available in active markets for identical assets or liabilities as of the reporting date. The types of assets and liabilities included in Level 1 are highly liquid and actively traded instruments with quoted prices.
	Level 2 -	Pricing inputs are other than quoted prices in active markets, but are either directly or indirectly observable as of the reporting date. The types of assets and liabilities included in Level 2 are typically either comparable to actively traded securities or contracts, or priced with discounted cash flow or option pricing models using highly observable inputs.
	Level 3 -	Significant inputs to pricing have little or no observability as of the reporting date. The types of assets and liabilities included in Level 3 are those valued with models requiring significant management judgment or estimation.
	Specific valuation methods include the following:
	Cash equivalents, accounts receivable, accounts payable, and short-term borrowings carrying amounts approximated the fair value because of the short-term maturity of the instruments.
	Long-term debt fair values were estimated using the published quoted market price, if available, or the discounted cash flow analysis, based on the current rates available using a risk-free rate (a U.S. Treasury securities yield curve) plus a risk premium of 1.19%.
	Advances for construction fair values were estimated using broker quotes from companies that frequently purchase these investments.
		September 30, 2013
				Fair Value
		Cost		Level 1		Level 2		Level 3		Total
	Money Market Investment	$	48,847	$	48,847					$	48,847
	Total	$	48,847	$	48,847					$	48,847
	Long -term debt, including current maturities	$	478,240	$	—	$	570,058	$	—	$	570,058
	Advances for construction	184,879		—		71,242		—		71,242
	Total	$	663,119	$	—	$	641,300	$	—	$	641,300
		December 31, 2012
				Fair Value
		Cost		Level 1		Level 2		Level 3		Total
	Long -term debt, including current maturities	$	481,250	$	—	$	613,211	$	—	$	613,211
	Advances for construction	187,584		—		70,914		—		70,914
	Total	$	668,834	$	—	$	684,125	$	—	$	684,125

Condensed_Consolidating_Financ

Condensed Consolidating Financial Statements	9 Months Ended
	Sep. 30, 2013
Condensed Consolidating Financial Statements	'
Condensed Consolidating Financial Statements	'
	Note 12. Condensed Consolidating Financial Statements
	On April 17, 2009, Cal Water issued $100 million aggregate principal amount of 5.875% First Mortgage Bonds due 2019, and on November 17, 2010, Cal Water issued $100 million aggregate principal amount of 5.500% First Mortgage Bonds due 2040.  Each series of Cal Water’s First Mortgage Bonds is fully and unconditionally guaranteed by the Company.  As a result of these guarantee arrangements, we are required to present the following condensed consolidating financial information.
	The tables below present the condensed consolidating balance sheets as of September 30, 2013 and December 31, 2012, the condensed consolidating statements of income for the three and nine months ended September 30, 2013 and 2012 and the condensed consolidating statements of cash flow for the nine months ended September 30, 2013 and 2012 of (i) California Water Service Group, the guarantor of the first mortgage bonds and the parent company; (ii) California Water Service Company, the issuer of the first mortgage bonds and a 100% owned subsidiary of California Water Service Group; and (iii) the other 100% owned subsidiaries of California Water Service Group.
	CALIFORNIA WATER SERVICE GROUP
	CONDENSED CONSOLIDATING BALANCE SHEET
	As of September 30, 2013
	(In thousands)
		Parent			Cal Water			All Other			Consolidating			Consolidated
		Company						Subsidiaries			Adjustments
	ASSETS
	Utility plant:
	Utility plant	$	1,246		$	2,013,475		$	183,049		$	(7,197	)	$	2,190,573
	Less accumulated depreciation and amortization	(150		)	(650,679		)	(36,109		)	1,587			(685,351		)
	Net utility plant	1,096			1,362,796			146,940			(5,610		)	1,505,222
	Current assets:
	Cash and cash equivalents	4,272			42,545			2,030			—			48,847
	Receivables and unbilled revenue, net	—			100,810			4,833			—			105,643
	Receivables from affiliates	28,964			5,539			181			(34,684		)	—
	Other current assets	73			15,038			951			—			16,062
	Total current assets	33,309			163,932			7,995			(34,684		)	170,552
	Other assets:
	Regulatory assets	—			352,232			2,647			—			354,879
	Investments in affiliates	546,123			—			—			(546,123		)	—
	Long-term affiliate notes receivable	30,252			—			—			(30,252		)	—
	Other assets	1,196			44,610			7,179			(205		)	52,780
	Total other assets	577,571			396,842			9,826			(576,580		)	407,659
		$	611,976		$	1,923,570		$	164,761		$	(616,874	)	$	2,083,433
	CAPITALIZATION AND LIABILITIES
	Capitalization:
	Common stockholders’ equity	$	600,254		$	500,359		$	51,271		$	(551,630	)	$	600,254
	Affiliate long-term debt	—			—			30,252			(30,252		)	—
	Long-term debt, less current maturities	—			428,878			1,349			—			430,227
	Total capitalization	600,254			929,237			82,872			(581,882		)	1,030,481
	Current liabilities:
	Current maturities of long-term debt	—			46,129			1,884			—			48,013
	Short-term borrowings	11,515			—			—			—			11,515
	Payables to affiliates	24			180			34,480			(34,684		)	—
	Accounts payable	—			57,434			2,980			—			60,414
	Accrued expenses and other liabilities	762			75,168			1,059			82			77,071
	Total current liabilities	12,301			178,911			40,403			(34,602		)	197,013
	Unamortized investment tax credits	—			2,180			—			—			2,180
	Deferred income taxes, net	(579		)	164,716			4,344			(390		)	168,091
	Pension and postretirement benefits other than pensions	—			247,335			—			—			247,335
	Regulatory and other liabilities	—			82,416			8,769			—			91,185
	Advances for construction	—			184,110			769			—			184,879
	Contributions in aid of construction	—			134,665			27,604			—			162,269
		$	611,976		$	1,923,570		$	164,761		$	(616,874	)	$	2,083,433
	CALIFORNIA WATER SERVICE GROUP
	CONDENSED CONSOLIDATING BALANCE SHEET
	As of December 31, 2012
	(In thousands)
		Parent			Cal Water			All Other			Consolidating			Consolidated
		Company						Subsidiaries			Adjustments
	ASSETS
	Utility plant:
	Utility plant	$	606		$	1,927,190		$	175,764		$	(7,197	)	$	2,096,363
	Less accumulated depreciation and amortization	(108		)	(607,992		)	(32,710		)	1,503			(639,307		)
	Net utility plant	498			1,319,198			143,054			(5,694		)	1,457,056
	Current assets:
	Cash and cash equivalents	1,470			34,609			2,711			—			38,790
	Receivables, net	—			87,482			3,833			—			91,315
	Receivables from affiliates	19,367			3,195			1,152			(23,714		)	—
	Other current assets	—			15,535			924			—			16,459
Total current assets	20,837			140,821			8,620			(23,714		)	146,564
Other assets:
Regulatory assets	—			341,877			2,542			—			344,419
Investments in affiliates	492,188			—			—			(492,188		)	—
Long-term affiliate notes receivable	31,218			7,781			—			(38,999		)	—
Other assets	1,023			40,005			7,062			(205		)	47,885
Total other assets	524,429			389,663			9,604			(531,392		)	392,304
	$	545,764		$	1,849,682		$	161,278		$	(560,800	)	$	1,995,924
CAPITALIZATION AND LIABILITIES
Capitalization:
Common stockholders’ equity	$	473,712		$	442,923		$	54,774		$	(497,697	)	$	473,712
Affiliate long-term debt	7,781			—			31,218			(38,999		)	—
Long-term debt, less current maturities	—			431,433			3,034			—			434,467
Total capitalization	481,493			874,356			89,026			(536,696		)	908,179
Current liabilities:
Current maturities of long-term debt	—			46,104			679			—			46,783
Short-term borrowings	64,475			25,000			—			—			89,475
Payables to affiliates	77			1,152			22,485			(23,714		)	—
Accounts payable	—			41,352			5,847			—			47,199
Accrued expenses and other liabilities	298			58,293			1,019			—			59,610
Total current liabilities	64,850			171,901			30,030			(23,714		)	243,067
Unamortized investment tax credits	—			2,180			—			—			2,180
Deferred income taxes, net	(579		)	155,481			4,334			(390		)	158,846
Pension and postretirement benefits other than pensions	—			244,901			—			—			244,901
Regulatory and other liabilities	—			83,942			8,651			—			92,593
Advances for construction	—			186,753			831			—			187,584
Contributions in aid of construction	—			130,168			28,406			—			158,574
	$	545,764		$	1,849,682		$	161,278		$	(560,800	)	$	1,995,924
CALIFORNIA WATER SERVICE GROUP
CONDENSED CONSOLIDATING STATEMENT OF INCOME
For the three months ended September 30, 2013
(In thousands)
	Parent			Cal Water			All Other			Consolidating			Consolidated
	Company						Subsidiaries			Adjustments
Operating revenue	$	—		$	174,699		$	9,705		$	—		$	184,404
Operating expenses:
Operations:
Water production costs	—			67,981			2,633			—			70,614
Administrative and general	—			22,354			2,316			—			24,670
Other operations	—			15,883			1,900			(126		)	17,657
Maintenance	—			4,382			193			—			4,575
Depreciation and amortization	14			13,714			805			(28		)	14,505
Income tax (benefit) expense	(17		)	10,721			107			354			11,165
Property and other taxes	—			4,680			734			—			5,414
Total operating (income) expenses	(3		)	139,715			8,688			200			148,600
Net operating income (loss)	3			34,984			1,017			(200		)	35,804
Other Income and Expenses:
Non-regulated revenue	572			3,385			475			(783		)	3,649
Non-regulated expense, net	—			(2,515		)	(310		)	—			(2,825		)
Income tax (expense) benefit on other income and expense	(232		)	(355		)	(85		)	342			(330		)
Net other income (expense)	340			515			80			(441		)	494
Interest:
Interest expense	30			7,608			707			(658		)	7,687
Less: capitalized interest	—			(495		)	(45		)	—			(540		)
Net interest expense	30			7,113			662			(658		)	7,147
Equity earnings of subsidiaries	28,838			—			—			(28,838		)	—
Net income (loss)	$	29,151		$	28,386		$	435		$	(28,821	)	$	29,151
CALIFORNIA WATER SERVICE GROUP
CONDENSED CONSOLIDATING STATEMENT OF INCOME
For the nine months ended September 30, 2013
(In thousands)
	Parent			Cal Water			All Other			Consolidating			Consolidated
	Company						Subsidiaries			Adjustments
Operating revenue	$	—		$	425,860		$	24,543		$	—		$	450,403
Operating expenses:
Operations:
Water production costs	—			164,524			7,432			—			171,956
Administrative and general	—			65,423			7,683			—			73,106
Other operations	—			45,490			5,220			(378		)	50,332
Maintenance	—			12,376			520			—			12,896
Depreciation and amortization	42			41,168			2,499			(84		)	43,625
Income tax (benefit) expense	(246		)	19,807			(1,064		)	1,070			19,567
Property and other taxes	—			14,549			2,015			—			16,564
Total operating (income) expenses	(204		)	363,337			24,305			608			388,046
Net operating income (loss)	204			62,523			238			(608		)	62,357
Other Income and Expenses:
Non-regulated revenue	1,739			9,572			1,415			(2,340		)	10,386
Non-regulated expense, net	—			(7,308		)	(1,174		)	—			(8,482		)
Income tax (expense) on other income and expense	(708		)	(923		)	(169		)	1,035			(765		)
Net other income (expense)	1,031			1,341			72			(1,305		)	1,139
Interest:
Interest expense	563			22,966			1,961			(1,963		)	23,527
Less: capitalized interest	—			(1,279		)	(340		)	—			(1,619		)
Net interest expense	563			21,687			1,621			(1,963		)	21,908
Equity earnings of subsidiaries	40,916			—			—			(40,916		)	—
Net income (loss)	$	41,588		$	42,177		$	(1,311	)	$	(40,866	)	$	41,588
CALIFORNIA WATER SERVICE GROUP
CONDENSED CONSOLIDATING STATEMENT OF INCOME
For the three months ended September 30, 2012
(In thousands)
	Parent			Cal Water			All Other			Consolidating			Consolidated
	Company						Subsidiaries			Adjustments
Operating revenue	$	—		$	168,680		$	9,455		$	—		$	178,135
Operating expenses:
Operations:
Water production costs	—			63,647			2,842			—			66,489
Administrative and general	—			21,639			2,286			—			23,925
Other operations	—			16,177			1,607			(126		)	17,658
Maintenance	—			4,238			139			—			4,377
Depreciation and amortization	—			13,051			699			(30		)	13,720
Income tax (benefit) expense	(150		)	9,831			372			334			10,387
Property and other taxes	—			4,552			666			—			5,218
Total operating expenses	(150		)	133,135			8,611			178			141,774
Net operating income	150			35,545			844			(178		)	36,361
Other Income and Expenses:
Non-regulated revenue	474			3,372			617			(707		)	3,756
Non-regulated expense, net	—			(2,217		)	(483		)	3			(2,697		)
Income tax (expense) on other income and expense	(193		)	(469		)	(82		)	322			(422		)
Net other income	281			686			52			(382		)	637
Interest:
Interest expense	368			7,702			535			(581		)	8,024
Less: capitalized interest	—			(505		)	(293		)	—			(798		)
Net interest expense	368			7,197			242			(581		)	7,226
Equity earnings of subsidiaries	29,709			—			—			(29,709		)	—
Net income (loss)	$	29,772		$	29,034		$	654		$	(29,688	)	$	29,772
CALIFORNIA WATER SERVICE GROUP
CONDENSED CONSOLIDATING STATEMENT OF INCOME
For the nine months ended September 30, 2012
(In thousands)
	Parent			Cal Water			All Other			Consolidating			Consolidated
	Company						Subsidiaries			Adjustments
Operating revenue	$	—		$	413,796		$	24,640		$	—		$	438,436
Operating expenses:
Operations:
Water production costs	—			150,396			7,723			—			158,119
Administrative and general	—			62,043			7,067			—			69,110
Other operations	—			54,584			5,008			(379		)	59,213
Maintenance	—			14,247			495			—			14,742
Depreciation and amortization	—			39,393			2,079			(89		)	41,383
Income tax (benefit) expense	(416		)	19,094			(198		)	997			19,477
Property and other taxes	—			11,819			1,983			—			13,802
Total operating expenses	(416		)	351,576			24,157			529			375,846
Net operating income (loss)	416			62,220			483			(529		)	62,590
Other Income and Expenses:
Non-regulated revenue	1,429			10,867			1,805			(2,158		)	11,943
Non-regulated expense, net	—			(7,072		)	(1,422		)	3			(8,491		)
Income tax (expense) on other income and expense	(582		)	(1,545		)	(216		)	960			(1,383		)
Net other income	847			2,250			167			(1,195		)	2,069
Interest:
Interest expense	1,022			22,648			1,594			(1,780		)	23,484
Less: capitalized interest	—			(1,785		)	(862		)	—			(2,647		)
Net interest expense	1,022			20,863			732			(1,780		)	20,837
Equity earnings of subsidiaries	43,581			—			—			(43,581		)	—
Net income (loss)	$	43,822		$	43,607		$	(82	)	$	(43,525	)	$	43,822
CALIFORNIA WATER SERVICE GROUP
CONDENSED CONSOLIDATING STATEMENT OF CASH FLOWS
For the nine months ended September 30, 2013
(In thousands)
	Parent			Cal Water			All Other			Consolidating			Consolidated
	Company						Subsidiaries			Adjustments
Operating activities:
Net income (loss)	$	41,588		$	42,177		$	(1,311	)	$	(40,866	)	$	41,588
Adjustments to reconcile net income (loss) to net cash provided by (used in) operating activities:
Equity earnings of subsidiaries	(40,916		)	—			—			40,916			—
Dividends received from affiliates	21,981			—			—			(21,981		)	—
Depreciation and amortization	42			42,509			2,600			(84		)	45,067
Change in value of life insurance contracts	—			(1,147		)	—			—			(1,147		)
Other changes in noncurrent assets and liabilities	1,164			12,415			(29		)	(49		)	13,501
Changes in operating assets and liabilities	390			4,220			(1,803		)	83			2,890
Net cash provided by (used in) operating activities	24,249			100,174			(543		)	(21,981		)	101,899
Investing activities:
Utility plant expenditures	(640		)	(84,688		)	(9,454		)	—			(94,782		)
Investment in affiliates	(35,000		)	—			—			35,000			—
Net changes in affiliate advances	(9,583		)	(2,359		)	1,141			10,801			—
Repayment of affiliates long-term debt	913			7,797			—			(8,710		)	—
Purchase of life insurance	—			(3,204		)	—			—			(3,204		)
Restricted cash and other changes, net	—			1,148			—			—			1,148
Net cash provided by (used in) investing activities	(44,310		)	(81,306		)	(8,313		)	37,091			(96,838		)
Financing Activities:
Short-term borrowings	15,315			20,000			—			—			35,315
Repayment of short-term borrowings	(68,275		)	(45,000		)	—			—			(113,275		)
Proceeds from long-term debt	—			—			48			—			48
Repayment of long-term debt	—			(2,531		)	(527		)	—			(3,058		)
Net changes in affiliate advances	—			(972		)	11,773			(10,801		)	—
Repayment of affiliates long-term debt	(7,796		)	—			(914		)	8,710			—
Advances and contributions in aid for construction	—			7,545			32			—			7,577
Refunds of advances for construction	—			(5,184		)	(46		)	—			(5,230		)
Dividends paid to non-affiliates	(21,981		)	—			—			—			(21,981		)
Dividends paid to affiliates	—			(19,790		)	(2,191		)	21,981			—
Issuance of common stock	105,600			—			—			—			105,600
Investment from affiliates	—			35,000			—			(35,000		)	—
Net cash (used in) provided by financing activities	22,863			(10,932		)	8,175			(15,110		)	4,996
Change in cash and cash equivalents	2,802			7,936			(681		)	—			10,057
Cash and cash equivalents at beginning of period	1,470			34,609			2,711			—			38,790
Cash and cash equivalents at end of period	$	4,272		$	42,545		$	2,030		$	—		$	48,847
CALIFORNIA WATER SERVICE GROUP
CONDENSED CONSOLIDATING STATEMENT OF CASH FLOWS
For the nine months ended September 30, 2012
(In thousands)
	Parent			Cal Water			All Other			Consolidating			Consolidated
	Company						Subsidiaries			Adjustments
Operating activities:
Net income (loss)	$	43,822		$	43,607		$	(82	)	$	(43,525	)	$	43,822
Adjustments to reconcile net income (loss) to net cash provided by (used in) operating activities:
Equity earnings of subsidiaries	(43,581		)	—			—			43,581			—
Dividends received from affiliates	19,785			—			—			(19,785		)	—
Depreciation and amortization	—			40,604			2,207			(89		)	42,722
Change in value of life insurance contracts	—			(2,244		)	—			—			(2,244		)
Other changes in noncurrent assets and liabilities	1,180			30,928			(3,815		)	118			28,411
Changes in operating assets and liabilities	(247		)	(10,557		)	(2,417		)	(85		)	(13,306		)
Net cash provided by (used in) operating activities	20,959			102,338			(4,107		)	(19,785		)	99,405
Investing activities:
Utility plant expenditures	—			(88,593		)	(11,007		)	—			(99,600		)
Investment in affiliates	—			—			—			—			—
Net changes in affiliate advances	(13,975		)	2,708			—			11,267			—
Repayment of affiliates long-term debt	411			36			—			(447		)	—
Purchase of life insurance	—			(3,199		)	—			—			(3,199		)
Restricted cash and other changes, net	—			1,553			—			—			1,553
Net cash provided by (used in) investing activities	(13,564		)	(87,495		)	(11,007		)	10,820			(101,246		)
Financing Activities:
Short-term borrowings	14,535			51,030			—			—			65,565
Repayment of short-term borrowings	(1,000		)	(51,030		)	—			—			(52,030		)
Proceeds from long-term debt	—			—			123			—			123
Repayment of long-term debt	—			(1,573		)	(550		)	—			(2,123		)
Net changes in affiliate advances	—			524			10,743			(11,267		)	—
Repayment of affiliates long-term debt	(36		)	—			(411		)	447			—
Advances and contributions in aid for construction	—			5,416			75			—			5,491
Refunds of advances for construction	—			(5,575		)	(57		)	—			(5,632		)
Dividends paid to non-affiliates	(19,785		)	—			—			—			(19,785		)
Dividends paid to affiliates	—			(17,671		)	(2,114		)	19,785			—
Issuance of common stock	—			—			—			—			—
Investment from affiliates	—			—			—			—			—
Net cash (used in) provided by financing activities	(6,286		)	(18,879		)	7,809			8,965			(8,391		)
Change in cash and cash equivalents	1,109			(4,036		)	(7,305		)	—			(10,232		)
Cash and cash equivalents at beginning of period	89			18,475			8,639			—			27,203
Cash and cash equivalents at end of period	$	1,198		$	14,439		$	1,334		$	—		$	16,971

Summary_of_Significant_Account1

Summary of Significant Accounting Policies (Policies)	9 Months Ended
	Sep. 30, 2013
Summary of Significant Accounting Policies	'
Revenue	'
	Revenue
	Revenue generally includes monthly cycle customer billings for regulated water and wastewater services at rates authorized by regulatory commissions (plus an estimate for water used between the customer’s last meter reading and the end of the accounting period) and billings to certain non-regulated customers at rates authorized by contract with government agencies.
	The Company’s regulated water and waste water revenue requirements are authorized by the Commissions in the states in which it operates. The revenue requirements are intended to provide the Company a reasonable opportunity to recover its operating costs and earn a return on investments.
	For metered customers, Cal Water recognizes revenue from rates which are designed and authorized by the California Public Utilities Commission (CPUC). Under the Water Revenue Adjustment Mechanism (WRAM), Cal Water records the adopted level of volumetric revenues, which would include recovery of cost of service and a return on investments, as established by the CPUC for metered accounts (adopted volumetric revenues). In addition to volumetric-based revenues, the revenue requirements approved by the CPUC include service charges, flat rate charges, and other items not subject to the WRAM. The adopted volumetric revenue considers the seasonality of consumption of water based upon historical averages. The variance between adopted volumetric revenues and actual billed volumetric revenues for metered accounts is recorded as a component of revenue with an offsetting entry to a regulatory asset or liability balancing account (tracked individually for each Cal Water district) subject to certain criteria under the accounting for regulated operations being met. The variance amount may be positive or negative and represents amounts that will be billed or refunded to customers in the future.
	Cost-recovery rates are designed to permit full recovery of certain costs allowed to be recovered by the Commissions. Cost-recovery rates such as the Modified Cost Balancing Account (MCBA) provides for recovery of adopted expense levels for purchased water, purchased power and pump taxes, as established by the CPUC. In addition, cost-recovery rates include recovery of cost related to water conservation programs and certain other operation expenses adopted by the CPUC. Variances (which include the effects of changes in both rate and volume for the MCBA) between adopted and actual costs are recorded as a component of revenue, as the amount of such variances will be recovered from or refunded to our customers at a later date. There is no markup for return or profit for cost-recovery expenses and they are generally recognized when expenses are incurred.
	The balances in the WRAM and MCBA assets and liabilities accounts will fluctuate on a monthly basis depending upon the variance between adopted and actual results. The recovery or refund of the WRAM is netted against the MCBA over- or under-recovery for the corresponding district and is interest bearing at the current 90 day commercial paper rate. At the end of any calendar year, Cal Water files with the CPUC to refund or collect the balance in the accounts. Most undercollected net WRAM and MCBA receivable balances are collected over 12 and 18 months. Cal Water defers net WRAM and MCBA operating revenues and associated costs whenever the net receivable balances are estimated to be collected more than 24 months after the respective reporting periods in which it was recognized. The deferred net WRAM and MCBA revenues and associated costs were determined using forecasts of rate payer consumption trends in future reporting periods and the timing of when the CPUC will authorize Cal Water’s filings to recover the undercollected balances. Deferred net WRAM and MCBA revenues and associated costs will be recognized as revenues and costs in future periods when collection is within twenty-four months of the respective reporting period.
	The change to deferred net WRAM and MCBA balances during the nine months ended September 30, 2013 was:
		Operating			Operating			Income Before
		Revenues			Costs			Income Taxes
	Net WRAM and MCBA deferral as of December 31, 2012	$	882		$	719		$	163
	Less: reversal of prior year deferral during the nine months ended September 30, 2013	(1,911		)	(1,603		)	(308		)
	Add: net WRAM and MCBA deferral during the nine months ended September 30, 2013	2,764			2,375			389
	Net amount during the nine months ended September 30, 2013	853			772			81
	Net WRAM and MCBA deferral as of September 30, 2013	$	1,735		$	1,491		$	244
	The change to deferred net WRAM and MCBA balances during the nine months ended September 30, 2012 was:
		Operating			Operating			Income Before
		Revenues			Costs			Income Taxes
	Net WRAM and MCBA deferral as of December 31, 2011	$	12,864		$	10,492		$	2,372
	Less: reversal of prior year deferral during the nine months ended September 30, 2012	(12,295		)	(10,027		)	(2,268		)
	Add: net WRAM and MCBA deferral during the nine months ended September 30, 2012	939			766			173
	Net amount during the nine months ended September 30, 2012	(11,356		)	(9,261		)	(2,095		)
	Net WRAM and MCBA deferral as of September 30, 2012	$	1,508		$	1,231		$	277
	The net WRAM and MCBA under- or overcollected balances are:
		September 30,			December 31,
		2013			2012
	Net short-term regulatory balancing accounts (receivable)	$	27,047		$	34,020
	Net long-term regulatory assets (receivable)	21,925			12,051
	Total regulatory assets	$	48,972		$	46,071
	Net short-term regulatory balancing accounts (liability)	$	174		$	371
	Net long-term regulatory liability	108			119
	Total regulatory liabilities	$	282		$	490
	Flat rate customers are billed in advance at the beginning of the service period. The revenue is prorated so that the portion of revenue applicable to the current period is included in that period’s revenue, with the balance recorded as unearned revenue on the balance sheet and recognized as revenue when earned in the subsequent accounting period. Unearned revenue liability was $1.5 million and $1.7 million as of September 30, 2013 and December 31, 2012, respectively. This liability is included in “accrued expenses and other liabilities” on the condensed consolidated balance sheets.
Cash and Cash Equivalents	'
	Cash and Cash Equivalents
	Cash equivalents include highly liquid investments with maturities of three months or less.  Cash and cash equivalents was $48.8 million and $38.8 million as of September 30, 2013 and December 31, 2012, respectively.  Restricted cash is included in “taxes, prepaid expenses and other assets” and was $1.1 million and $2.3 million as of September 30, 2013 and December 31, 2012, respectively.
Adoption of New Accounting Standards	'
	Adoption of New Accounting Standards
	On February 1, 2013, the Financial Accounting Standards Board issued an accounting standards update (ASU) for the recognition, measurement, and disclosure of obligations resulting from joint and several liability arrangements.  The ASU would impact the Company’s recognition, measurement, and disclosure requirements for guarantees of third party debt.  The ASU effective date for the Company’s interim and annual reporting is January 1, 2014.  The Company has completed a review of all contracts and has not identified any joint and several liability arrangements.

Summary_of_Significant_Account2

Summary of Significant Accounting Policies (Tables)	9 Months Ended
	Sep. 30, 2013
Summary of Significant Accounting Policies	'
Schedule of change to net WRAM and MCBA deferred balances	'
	The change to deferred net WRAM and MCBA balances during the nine months ended September 30, 2013 was:
		Operating			Operating			Income Before
		Revenues			Costs			Income Taxes
	Net WRAM and MCBA deferral as of December 31, 2012	$	882		$	719		$	163
	Less: reversal of prior year deferral during the nine months ended September 30, 2013	(1,911		)	(1,603		)	(308		)
	Add: net WRAM and MCBA deferral during the nine months ended September 30, 2013	2,764			2,375			389
	Net amount during the nine months ended September 30, 2013	853			772			81
	Net WRAM and MCBA deferral as of September 30, 2013	$	1,735		$	1,491		$	244
	The change to deferred net WRAM and MCBA balances during the nine months ended September 30, 2012 was:
		Operating			Operating			Income Before
		Revenues			Costs			Income Taxes
	Net WRAM and MCBA deferral as of December 31, 2011	$	12,864		$	10,492		$	2,372
	Less: reversal of prior year deferral during the nine months ended September 30, 2012	(12,295		)	(10,027		)	(2,268		)
	Add: net WRAM and MCBA deferral during the nine months ended September 30, 2012	939			766			173
	Net amount during the nine months ended September 30, 2012	(11,356		)	(9,261		)	(2,095		)
	Net WRAM and MCBA deferral as of September 30, 2012	$	1,508		$	1,231		$	277
Schedule of net WRAM and MCBA balances	'
		September 30,			December 31,
		2013			2012
	Net short-term regulatory balancing accounts (receivable)	$	27,047		$	34,020
	Net long-term regulatory assets (receivable)	21,925			12,051
	Total regulatory assets	$	48,972		$	46,071
	Net short-term regulatory balancing accounts (liability)	$	174		$	371
	Net long-term regulatory liability	108			119
	Total regulatory liabilities	$	282		$	490

Equity_Tables

Equity (Tables)	9 Months Ended
	Sep. 30, 2013
Equity	'
Schedule of changes in equity	'
	The Company’s changes in equity for the nine months ended September 30, 2013 were as follows:
		Total Stockholders’ Equity
	Balance at December 31, 2012	$	473,712
	Common stock issued, net	105,600
	Share-based compensation expense	1,335
	Common stock dividends declared	(21,981		)
	Net income	41,588
	Balance at September 30, 2013	$	600,254

Earnings_Per_Share_Calculation1

Earnings Per Share Calculations (Tables)	9 Months Ended
	Sep. 30, 2013
Earnings Per Share Calculations	'
Schedule of RSAs which were dilutive and anti-dilutive	'
		Three months Ended September 30
		2013		2012
	Net income available to common stockholders	$	29,151	$	29,772
	Weighted average common shares, basic	47,737		41,905
	Dilutive common stock appreciation rights (treasury method)	33		—
	Shares used for dilutive computation	47,770		41,905
	Net income per share - basic	$	0.61	$	0.71
	Net income per share - diluted	$	0.61	$	0.71
		Nine months Ended September 30
		2013		2012
	Net income available to common stockholders	$	41,588	$	43,822
	Weighted average common shares, basic	45,927		41,886
	Dilutive common stock appreciation rights (treasury method)	30		—
	Shares used for dilutive computation	45,957		41,886
	Net income per share - basic	$	0.91	$	1.05
	Net income per share - diluted	$	0.9	$	1.05

Pension_Plan_and_Other_Postret1

Pension Plan and Other Postretirement Benefits (Tables)	9 Months Ended
	Sep. 30, 2013
Pension Plan and Other Postretirement Benefits	'
Components of net periodic benefit costs for the pension and other postretirement plans	'
		Three months Ended September 30
		Pension Plan						Other Benefits
		2013			2012			2013			2012
	Service cost	$	4,019		$	3,863		$	1,636		$	1,374
	Interest cost	4,140			3,822			1,121			986
	Expected return on plan assets	(3,559		)	(2,890		)	(600		)	(458		)
	Recognized net initial APBO (1)	N/A			N/A			3			69
	Amortization of prior service cost	1,542			1,571			21			29
	Recognized net actuarial loss	2,404			2,000			961			793
	Net periodic benefit cost	$	8,546		$	8,366		$	3,142		$	2,793
		Nine months Ended September 30
		Pension Plan						Other Benefits
		2013			2012			2013			2012
	Service cost	$	13,335		$	11,588		$	5,025		$	4,121
	Interest cost	12,266			11,465			3,339			2,958
	Expected return on plan assets	(10,689		)	(8,669		)	(1,796		)	(1,374		)
	Recognized net initial APBO (1)	N/A			N/A			7			207
	Amortization of prior service cost	4,624			4,712			61			87
	Recognized net actuarial loss	6,852			6,001			2,794			2,379
	Net periodic benefit cost	$	26,388		$	25,097		$	9,430		$	8,378
	(1)      APBO - Accumulated postretirement benefit obligation

Fair_Value_of_Financial_Assets1

Fair Value of Financial Assets and Liabilities (Tables)	9 Months Ended
	Sep. 30, 2013
Fair Value of Financial Assets and Liabilities	'
Schedule of fair value of long-term debt, including current maturities, and advances for construction	'
		September 30, 2013
				Fair Value
		Cost		Level 1		Level 2		Level 3		Total
	Money Market Investment	$	48,847	$	48,847					$	48,847
	Total	$	48,847	$	48,847					$	48,847
	Long -term debt, including current maturities	$	478,240	$	—	$	570,058	$	—	$	570,058
	Advances for construction	184,879		—		71,242		—		71,242
	Total	$	663,119	$	—	$	641,300	$	—	$	641,300
		December 31, 2012
				Fair Value
		Cost		Level 1		Level 2		Level 3		Total
	Long -term debt, including current maturities	$	481,250	$	—	$	613,211	$	—	$	613,211
	Advances for construction	187,584		—		70,914		—		70,914
	Total	$	668,834	$	—	$	684,125	$	—	$	684,125

Condensed_Consolidating_Financ1

Condensed Consolidating Financial Statements (Tables)	9 Months Ended
	Sep. 30, 2013
Condensed Consolidating Financial Statements	'
Schedule of Condensed Consolidating Balance Sheet	'
	As of September 30, 2013
	(In thousands)
		Parent			Cal Water			All Other			Consolidating			Consolidated
		Company						Subsidiaries			Adjustments
	ASSETS
	Utility plant:
	Utility plant	$	1,246		$	2,013,475		$	183,049		$	(7,197	)	$	2,190,573
	Less accumulated depreciation and amortization	(150		)	(650,679		)	(36,109		)	1,587			(685,351		)
	Net utility plant	1,096			1,362,796			146,940			(5,610		)	1,505,222
	Current assets:
	Cash and cash equivalents	4,272			42,545			2,030			—			48,847
	Receivables and unbilled revenue, net	—			100,810			4,833			—			105,643
	Receivables from affiliates	28,964			5,539			181			(34,684		)	—
	Other current assets	73			15,038			951			—			16,062
	Total current assets	33,309			163,932			7,995			(34,684		)	170,552
	Other assets:
	Regulatory assets	—			352,232			2,647			—			354,879
	Investments in affiliates	546,123			—			—			(546,123		)	—
	Long-term affiliate notes receivable	30,252			—			—			(30,252		)	—
	Other assets	1,196			44,610			7,179			(205		)	52,780
	Total other assets	577,571			396,842			9,826			(576,580		)	407,659
		$	611,976		$	1,923,570		$	164,761		$	(616,874	)	$	2,083,433
	CAPITALIZATION AND LIABILITIES
	Capitalization:
	Common stockholders’ equity	$	600,254		$	500,359		$	51,271		$	(551,630	)	$	600,254
	Affiliate long-term debt	—			—			30,252			(30,252		)	—
	Long-term debt, less current maturities	—			428,878			1,349			—			430,227
	Total capitalization	600,254			929,237			82,872			(581,882		)	1,030,481
	Current liabilities:
	Current maturities of long-term debt	—			46,129			1,884			—			48,013
	Short-term borrowings	11,515			—			—			—			11,515
	Payables to affiliates	24			180			34,480			(34,684		)	—
	Accounts payable	—			57,434			2,980			—			60,414
	Accrued expenses and other liabilities	762			75,168			1,059			82			77,071
	Total current liabilities	12,301			178,911			40,403			(34,602		)	197,013
	Unamortized investment tax credits	—			2,180			—			—			2,180
	Deferred income taxes, net	(579		)	164,716			4,344			(390		)	168,091
	Pension and postretirement benefits other than pensions	—			247,335			—			—			247,335
	Regulatory and other liabilities	—			82,416			8,769			—			91,185
	Advances for construction	—			184,110			769			—			184,879
	Contributions in aid of construction	—			134,665			27,604			—			162,269
		$	611,976		$	1,923,570		$	164,761		$	(616,874	)	$	2,083,433
	As of December 31, 2012
	(In thousands)
		Parent			Cal Water			All Other			Consolidating			Consolidated
		Company						Subsidiaries			Adjustments
	ASSETS
	Utility plant:
	Utility plant	$	606		$	1,927,190		$	175,764		$	(7,197	)	$	2,096,363
	Less accumulated depreciation and amortization	(108		)	(607,992		)	(32,710		)	1,503			(639,307		)
	Net utility plant	498			1,319,198			143,054			(5,694		)	1,457,056
	Current assets:
	Cash and cash equivalents	1,470			34,609			2,711			—			38,790
	Receivables, net	—			87,482			3,833			—			91,315
	Receivables from affiliates	19,367			3,195			1,152			(23,714		)	—
	Other current assets	—			15,535			924			—			16,459
	Total current assets	20,837			140,821			8,620			(23,714		)	146,564
	Other assets:
	Regulatory assets	—			341,877			2,542			—			344,419
	Investments in affiliates	492,188			—			—			(492,188		)	—
	Long-term affiliate notes receivable	31,218			7,781			—			(38,999		)	—
	Other assets	1,023			40,005			7,062			(205		)	47,885
	Total other assets	524,429			389,663			9,604			(531,392		)	392,304
	$	545,764		$	1,849,682		$	161,278		$	(560,800	)	$	1,995,924
CAPITALIZATION AND LIABILITIES
Capitalization:
Common stockholders’ equity	$	473,712		$	442,923		$	54,774		$	(497,697	)	$	473,712
Affiliate long-term debt	7,781			—			31,218			(38,999		)	—
Long-term debt, less current maturities	—			431,433			3,034			—			434,467
Total capitalization	481,493			874,356			89,026			(536,696		)	908,179
Current liabilities:
Current maturities of long-term debt	—			46,104			679			—			46,783
Short-term borrowings	64,475			25,000			—			—			89,475
Payables to affiliates	77			1,152			22,485			(23,714		)	—
Accounts payable	—			41,352			5,847			—			47,199
Accrued expenses and other liabilities	298			58,293			1,019			—			59,610
Total current liabilities	64,850			171,901			30,030			(23,714		)	243,067
Unamortized investment tax credits	—			2,180			—			—			2,180
Deferred income taxes, net	(579		)	155,481			4,334			(390		)	158,846
Pension and postretirement benefits other than pensions	—			244,901			—			—			244,901
Regulatory and other liabilities	—			83,942			8,651			—			92,593
Advances for construction	—			186,753			831			—			187,584
Contributions in aid of construction	—			130,168			28,406			—			158,574
	$	545,764		$	1,849,682		$	161,278		$	(560,800	)	$	1,995,924
Schedule of Condensed Consolidating Statement of Income	'
	For the three months ended September 30, 2013
	(In thousands)
		Parent			Cal Water			All Other			Consolidating			Consolidated
		Company						Subsidiaries			Adjustments
	Operating revenue	$	—		$	174,699		$	9,705		$	—		$	184,404
	Operating expenses:
	Operations:
	Water production costs	—			67,981			2,633			—			70,614
	Administrative and general	—			22,354			2,316			—			24,670
	Other operations	—			15,883			1,900			(126		)	17,657
	Maintenance	—			4,382			193			—			4,575
	Depreciation and amortization	14			13,714			805			(28		)	14,505
	Income tax (benefit) expense	(17		)	10,721			107			354			11,165
	Property and other taxes	—			4,680			734			—			5,414
	Total operating (income) expenses	(3		)	139,715			8,688			200			148,600
	Net operating income (loss)	3			34,984			1,017			(200		)	35,804
	Other Income and Expenses:
	Non-regulated revenue	572			3,385			475			(783		)	3,649
	Non-regulated expense, net	—			(2,515		)	(310		)	—			(2,825		)
	Income tax (expense) benefit on other income and expense	(232		)	(355		)	(85		)	342			(330		)
	Net other income (expense)	340			515			80			(441		)	494
	Interest:
	Interest expense	30			7,608			707			(658		)	7,687
	Less: capitalized interest	—			(495		)	(45		)	—			(540		)
	Net interest expense	30			7,113			662			(658		)	7,147
	Equity earnings of subsidiaries	28,838			—			—			(28,838		)	—
	Net income (loss)	$	29,151		$	28,386		$	435		$	(28,821	)	$	29,151
	For the nine months ended September 30, 2013
	(In thousands)
		Parent			Cal Water			All Other			Consolidating			Consolidated
		Company						Subsidiaries			Adjustments
	Operating revenue	$	—		$	425,860		$	24,543		$	—		$	450,403
	Operating expenses:
	Operations:
	Water production costs	—			164,524			7,432			—			171,956
	Administrative and general	—			65,423			7,683			—			73,106
	Other operations	—			45,490			5,220			(378		)	50,332
	Maintenance	—			12,376			520			—			12,896
	Depreciation and amortization	42			41,168			2,499			(84		)	43,625
	Income tax (benefit) expense	(246		)	19,807			(1,064		)	1,070			19,567
	Property and other taxes	—			14,549			2,015			—			16,564
	Total operating (income) expenses	(204		)	363,337			24,305			608			388,046
	Net operating income (loss)	204			62,523			238			(608		)	62,357
	Other Income and Expenses:
	Non-regulated revenue	1,739			9,572			1,415			(2,340		)	10,386
	Non-regulated expense, net	—			(7,308		)	(1,174		)	—			(8,482		)
	Income tax (expense) on other income and expense	(708		)	(923		)	(169		)	1,035			(765		)
	Net other income (expense)	1,031			1,341			72			(1,305		)	1,139
	Interest:
	Interest expense	563			22,966			1,961			(1,963		)	23,527
	Less: capitalized interest	—			(1,279		)	(340		)	—			(1,619		)
	Net interest expense	563			21,687			1,621			(1,963		)	21,908
	Equity earnings of subsidiaries	40,916			—			—			(40,916		)	—
	Net income (loss)	$	41,588		$	42,177		$	(1,311	)	$	(40,866	)	$	41,588
	For the three months ended September 30, 2012
	(In thousands)
		Parent			Cal Water			All Other			Consolidating			Consolidated
		Company						Subsidiaries			Adjustments
	Operating revenue	$	—		$	168,680		$	9,455		$	—		$	178,135
	Operating expenses:
	Operations:
	Water production costs	—			63,647			2,842			—			66,489
	Administrative and general	—			21,639			2,286			—			23,925
Other operations	—			16,177			1,607			(126		)	17,658
Maintenance	—			4,238			139			—			4,377
Depreciation and amortization	—			13,051			699			(30		)	13,720
Income tax (benefit) expense	(150		)	9,831			372			334			10,387
Property and other taxes	—			4,552			666			—			5,218
Total operating expenses	(150		)	133,135			8,611			178			141,774
Net operating income	150			35,545			844			(178		)	36,361
Other Income and Expenses:
Non-regulated revenue	474			3,372			617			(707		)	3,756
Non-regulated expense, net	—			(2,217		)	(483		)	3			(2,697		)
Income tax (expense) on other income and expense	(193		)	(469		)	(82		)	322			(422		)
Net other income	281			686			52			(382		)	637
Interest:
Interest expense	368			7,702			535			(581		)	8,024
Less: capitalized interest	—			(505		)	(293		)	—			(798		)
Net interest expense	368			7,197			242			(581		)	7,226
Equity earnings of subsidiaries	29,709			—			—			(29,709		)	—
Net income (loss)	$	29,772		$	29,034		$	654		$	(29,688	)	$	29,772
For the nine months ended September 30, 2012
(In thousands)
	Parent			Cal Water			All Other			Consolidating			Consolidated
	Company						Subsidiaries			Adjustments
Operating revenue	$	—		$	413,796		$	24,640		$	—		$	438,436
Operating expenses:
Operations:
Water production costs	—			150,396			7,723			—			158,119
Administrative and general	—			62,043			7,067			—			69,110
Other operations	—			54,584			5,008			(379		)	59,213
Maintenance	—			14,247			495			—			14,742
Depreciation and amortization	—			39,393			2,079			(89		)	41,383
Income tax (benefit) expense	(416		)	19,094			(198		)	997			19,477
Property and other taxes	—			11,819			1,983			—			13,802
Total operating expenses	(416		)	351,576			24,157			529			375,846
Net operating income (loss)	416			62,220			483			(529		)	62,590
Other Income and Expenses:
Non-regulated revenue	1,429			10,867			1,805			(2,158		)	11,943
Non-regulated expense, net	—			(7,072		)	(1,422		)	3			(8,491		)
Income tax (expense) on other income and expense	(582		)	(1,545		)	(216		)	960			(1,383		)
Net other income	847			2,250			167			(1,195		)	2,069
Interest:
Interest expense	1,022			22,648			1,594			(1,780		)	23,484
Less: capitalized interest	—			(1,785		)	(862		)	—			(2,647		)
Net interest expense	1,022			20,863			732			(1,780		)	20,837
Equity earnings of subsidiaries	43,581			—			—			(43,581		)	—
Net income (loss)	$	43,822		$	43,607		$	(82	)	$	(43,525	)	$	43,822
Schedule of Condensed Consolidating Statement of Cash Flows	'
	For the nine months ended September 30, 2013
	(In thousands)
		Parent			Cal Water			All Other			Consolidating			Consolidated
		Company						Subsidiaries			Adjustments
	Operating activities:
	Net income (loss)	$	41,588		$	42,177		$	(1,311	)	$	(40,866	)	$	41,588
	Adjustments to reconcile net income (loss) to net cash provided by (used in) operating activities:
	Equity earnings of subsidiaries	(40,916		)	—			—			40,916			—
	Dividends received from affiliates	21,981			—			—			(21,981		)	—
	Depreciation and amortization	42			42,509			2,600			(84		)	45,067
	Change in value of life insurance contracts	—			(1,147		)	—			—			(1,147		)
	Other changes in noncurrent assets and liabilities	1,164			12,415			(29		)	(49		)	13,501
	Changes in operating assets and liabilities	390			4,220			(1,803		)	83			2,890
	Net cash provided by (used in) operating activities	24,249			100,174			(543		)	(21,981		)	101,899
	Investing activities:
	Utility plant expenditures	(640		)	(84,688		)	(9,454		)	—			(94,782		)
	Investment in affiliates	(35,000		)	—			—			35,000			—
	Net changes in affiliate advances	(9,583		)	(2,359		)	1,141			10,801			—
	Repayment of affiliates long-term debt	913			7,797			—			(8,710		)	—
	Purchase of life insurance	—			(3,204		)	—			—			(3,204		)
	Restricted cash and other changes, net	—			1,148			—			—			1,148
	Net cash provided by (used in) investing activities	(44,310		)	(81,306		)	(8,313		)	37,091			(96,838		)
	Financing Activities:
	Short-term borrowings	15,315			20,000			—			—			35,315
	Repayment of short-term borrowings	(68,275		)	(45,000		)	—			—			(113,275		)
	Proceeds from long-term debt	—			—			48			—			48
	Repayment of long-term debt	—			(2,531		)	(527		)	—			(3,058		)
	Net changes in affiliate advances	—			(972		)	11,773			(10,801		)	—
	Repayment of affiliates long-term debt	(7,796		)	—			(914		)	8,710			—
	Advances and contributions in aid for construction	—			7,545			32			—			7,577
	Refunds of advances for construction	—			(5,184		)	(46		)	—			(5,230		)
	Dividends paid to non-affiliates	(21,981		)	—			—			—			(21,981		)
	Dividends paid to affiliates	—			(19,790		)	(2,191		)	21,981			—
	Issuance of common stock	105,600			—			—			—			105,600
	Investment from affiliates	—			35,000			—			(35,000		)	—
	Net cash (used in) provided by financing activities	22,863			(10,932		)	8,175			(15,110		)	4,996
	Change in cash and cash equivalents	2,802			7,936			(681		)	—			10,057
	Cash and cash equivalents at beginning of period	1,470			34,609			2,711			—			38,790
	Cash and cash equivalents at end of period	$	4,272		$	42,545		$	2,030		$	—		$	48,847
	For the nine months ended September 30, 2012
	(In thousands)
		Parent			Cal Water			All Other			Consolidating			Consolidated
		Company						Subsidiaries			Adjustments
	Operating activities:
	Net income (loss)	$	43,822		$	43,607		$	(82	)	$	(43,525	)	$	43,822
	Adjustments to reconcile net income (loss) to net cash provided by (used in) operating activities:
	Equity earnings of subsidiaries	(43,581		)	—			—			43,581			—
	Dividends received from affiliates	19,785			—			—			(19,785		)	—
	Depreciation and amortization	—			40,604			2,207			(89		)	42,722
	Change in value of life insurance contracts	—			(2,244		)	—			—			(2,244		)
	Other changes in noncurrent assets and liabilities	1,180			30,928			(3,815		)	118			28,411
	Changes in operating assets and liabilities	(247		)	(10,557		)	(2,417		)	(85		)	(13,306		)
	Net cash provided by (used in) operating activities	20,959			102,338			(4,107		)	(19,785		)	99,405
	Investing activities:
	Utility plant expenditures	—			(88,593		)	(11,007		)	—			(99,600		)
	Investment in affiliates	—			—			—			—			—
	Net changes in affiliate advances	(13,975		)	2,708			—			11,267			—
	Repayment of affiliates long-term debt	411			36			—			(447		)	—
	Purchase of life insurance	—			(3,199		)	—			—			(3,199		)
	Restricted cash and other changes, net	—			1,553			—			—			1,553
	Net cash provided by (used in) investing activities	(13,564		)	(87,495		)	(11,007		)	10,820			(101,246		)
	Financing Activities:
	Short-term borrowings	14,535			51,030			—			—			65,565
Repayment of short-term borrowings	(1,000		)	(51,030		)	—			—			(52,030		)
Proceeds from long-term debt	—			—			123			—			123
Repayment of long-term debt	—			(1,573		)	(550		)	—			(2,123		)
Net changes in affiliate advances	—			524			10,743			(11,267		)	—
Repayment of affiliates long-term debt	(36		)	—			(411		)	447			—
Advances and contributions in aid for construction	—			5,416			75			—			5,491
Refunds of advances for construction	—			(5,575		)	(57		)	—			(5,632		)
Dividends paid to non-affiliates	(19,785		)	—			—			—			(19,785		)
Dividends paid to affiliates	—			(17,671		)	(2,114		)	19,785			—
Issuance of common stock	—			—			—			—			—
Investment from affiliates	—			—			—			—			—
Net cash (used in) provided by financing activities	(6,286		)	(18,879		)	7,809			8,965			(8,391		)
Change in cash and cash equivalents	1,109			(4,036		)	(7,305		)	—			(10,232		)
Cash and cash equivalents at beginning of period	89			18,475			8,639			—			27,203
Cash and cash equivalents at end of period	$	1,198		$	14,439		$	1,334		$	—		$	16,971

Organization_and_Operations_an1

Organization and Operations and Basis of Presentation (Details)	9 Months Ended
	Sep. 30, 2013
	segment
Organization and Operations and Basis of Presentation	'
Ownership interest in subsidiaries (as a percent)	100.00%
Number of reportable segments	1

Summary_of_Significant_Account3

Summary of Significant Accounting Policies (Details) (USD $)	9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Dec. 31, 2012	Dec. 31, 2011
Revenue	'	'	'	'
Maturity period of commercial paper	'90 days	'	'	'
Period within which revenues and associated costs reported as net regulatory balancing accounts related to the WRAM and MCBA that are deferred, are Not expected to be collected	'24 months	'	'	'
Expected collection period for operating income reported as net regulatory balancing accounts related to the WRAM and MCBA that are deferred	'24 months	'	'	'
Unearned revenue liability	$1,500,000	'	$1,700,000	'
Operating Revenues	'	'	'	'
Net WRAM and MCBA deferral at the beginning of the period	882,000	12,864,000	'	'
Less: reversal of prior year deferral during the period	-1,911,000	-12,295,000	'	'
Add: net WRAM and MCBA deferral during the period	2,764,000	939,000	'	'
Net amount during the period	853,000	-11,356,000	'	'
Net WRAM and MCBA deferral at the end of the period	1,735,000	1,508,000	'	'
Operating Costs	'	'	'	'
Net WRAM and MCBA deferral at the beginning of the period	719,000	10,492,000	'	'
Less: reversal of prior year deferral during the period	-1,603,000	-10,027,000	'	'
Add: net WRAM and MCBA deferral during the period	2,375,000	766,000	'	'
Net amount during the period	772,000	-9,261,000	'	'
Net WRAM and MCBA deferral at the end of the period	1,491,000	1,231,000	'	'
Income Before Income Taxes	'	'	'	'
Net WRAM and MCBA deferral at the beginning of the period	163,000	2,372,000	'	'
Less: reversal of prior year deferral during the period	-308,000	-2,268,000	'	'
Add: net WRAM and MCBA deferral during the period	389,000	173,000	'	'
Net amount during the period	81,000	-2,095,000	'	'
Net WRAM and MCBA deferral at the end of the period	244,000	277,000	'	'
Markup for return or profit for cost-recovery expenses	0	'	'	'
Regulatory Assets and Liabilities	'	'	'	'
Net short-term regulatory balancing accounts (receivable)	27,047,000	'	34,020,000	'
Net long-term regulatory assets (receivable)	354,879,000	'	344,419,000	'
Net short-term regulatory balancing accounts (liability)	1,699,000	'	5,018,000	'
Cash and Cash Equivalents	'	'	'	'
Cash and cash equivalents	48,847,000	16,971,000	38,790,000	27,203,000
Restricted cash	1,100,000	'	2,300,000	'
Minimum	'	'	'	'
Regulatory Assets and Liabilities	'	'	'	'
Expected collection period for undercollected net WRAM and MCBA receivables	'12 months	'	'	'
Maximum	'	'	'	'
Regulatory Assets and Liabilities	'	'	'	'
Expected collection period for undercollected net WRAM and MCBA receivables	'18 months	'	'	'
Net WRAM and MCBA accounts payable	'	'	'	'
Regulatory Assets and Liabilities	'	'	'	'
Net short-term regulatory balancing accounts (liability)	174,000	'	371,000	'
Net long-term regulatory liability	108,000	'	119,000	'
Total regulatory liabilities	282,000	'	490,000	'
Net WRAM and MCBA accounts receivable	'	'	'	'
Regulatory Assets and Liabilities	'	'	'	'
Net short-term regulatory balancing accounts (receivable)	27,047,000	'	34,020,000	'
Net long-term regulatory assets (receivable)	21,925,000	'	12,051,000	'
Total regulatory assets	$48,972,000	'	$46,071,000	'

Stockbased_Compensation_Detail

Stock-based Compensation (Details) (USD $)

9 Months Ended

0 Months Ended

9 Months Ended

3 Months Ended

9 Months Ended

9 Months Ended

12 Months Ended

9 Months Ended

In Millions, except Share data, unless otherwise specified

Sep. 30, 2013

Sep. 30, 2012

Mar. 01, 2013

Sep. 30, 2013

Sep. 30, 2013

Sep. 30, 2013

Sep. 30, 2013

Sep. 30, 2012

Sep. 30, 2013

Sep. 30, 2012

Apr. 27, 2005

Sep. 30, 2013

Sep. 30, 2012

Sep. 30, 2013

Sep. 30, 2013

Dec. 31, 2012

Sep. 30, 2013

Sep. 30, 2013

Restricted Stock Awards (RSAs)

Restricted Stock Awards (RSAs)

Restricted Stock Unit Awards (RSUs)

Restricted Stock Unit Awards (RSUs)

Restricted Stock Unit Awards (RSUs)

Restricted Stock Unit Awards (RSUs)

Equity Incentive Plan

Equity Incentive Plan

Equity Incentive Plan

Equity Incentive Plan

Equity Incentive Plan

Equity Incentive Plan

Equity Incentive Plan

Equity Incentive Plan

Equity Incentive Plan

Equity Incentive Plan

Equity Incentive Plan

Equity Incentive Plan

Officers

Officers

Officers

Officers

Restricted Stock Awards (RSAs)

Restricted Stock Awards (RSAs)

Restricted Stock Awards (RSAs)

Restricted Stock Awards (RSAs)

Restricted Stock Awards (RSAs)

Restricted Stock Unit Awards (RSUs)

Restricted Stock Unit Awards (RSUs)

Maximum

Minimum

Director

Employees

Employees

Officers

Stock-based Compensation

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Shares authorized to be issued under the plan

'

'

'

'

'

'

'

'

'

'

2,000,000

'

'

'

'

'

'

'

Awards granted (in shares)

72,891

98,422

50,267

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Awards cancelled (in shares)

'

'

'

'

'

'

'

'

'

'

'

0

0

'

'

'

'

'

Vesting period

'

'

'

'

'

'

'

'

'

'

'

'

'

'12 months

'36 months

'48 months

'3 years

'

Weighted average grant date fair value (in dollars per share)

'

'

'

'

'

'

'

'

'

'

'

$20.66

$17.96

'

'

'

'

$20.62

Expiration period of award

'

'

'

'3 years

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Options vested on anniversary date (as a percent)

'

'

'

'

200.00%

0.00%

'

'

'

'

'

'

'

'

'

'

'

'

Compensation expense

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Recorded compensation costs for the RSAs and RSUs

'

'

'

'

'

'

$0.50

$0.30

$1.30

$1.10

'

'

'

'

'

'

'

'

Equity_Details

Equity (Details) (USD $)

0 Months Ended

3 Months Ended

9 Months Ended

1 Months Ended

3 Months Ended

9 Months Ended

1 Months Ended

3 Months Ended

9 Months Ended

Mar. 26, 2013

Sep. 30, 2013

Sep. 30, 2012

Sep. 30, 2013

Sep. 30, 2012

Apr. 30, 2013

Sep. 30, 2013

Sep. 30, 2012

Sep. 30, 2013

Sep. 30, 2012

Apr. 30, 2013

Sep. 30, 2013

Sep. 30, 2012

Sep. 30, 2013

Sep. 30, 2012

California Water Service Group

California Water Service Group

California Water Service Group

California Water Service Group

California Water Service Group

Cal Water

Cal Water

Cal Water

Cal Water

Cal Water

Changes in total stockholders' equity

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Balance at the beginning of the period

'

'

'

$473,712,000

'

'

'

'

$473,712,000

'

'

'

'

$442,923,000

'

Common stock issued, net

'

'

'

105,600,000

'

'

'

'

'

'

'

'

'

'

'

Share-based compensation expense

'

'

'

1,335,000

'

'

'

'

'

'

'

'

'

'

'

Common stock dividends declared

'

'

'

-21,981,000

'

'

'

'

'

'

'

'

'

'

'

Net income

'

29,151,000

29,772,000

41,588,000

43,822,000

'

29,151,000

29,772,000

41,588,000

43,822,000

'

28,386,000

29,034,000

42,177,000

43,607,000

Balance at the end of the period

'

600,254,000

'

600,254,000

'

'

600,254,000

'

600,254,000

'

'

500,359,000

'

500,359,000

'

Common stock sold in an underwritten public offering

5,750,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Proceeds from common stock sold in an underwritten public offering

105,600,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Underwriting discounts and commissions and offering expenses

5,100,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Equity

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Repayment on line of credit

'

'

'

'

'

$68,300,000

'

'

'

'

$25,000,000

'

'

'

'

Earnings_Per_Share_Calculation2

Earnings Per Share Calculations (Details) (USD $)	3 Months Ended		9 Months Ended
In Thousands, except Share data, unless otherwise specified	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Earnings Per Share Calculations	'	'	'	'
Net income available to common stockholders	$29,151	$29,772	$41,588	$43,822
Weighted average common shares, basic	47,737,000	41,905,000	45,927,000	41,886,000
Dilutive shares	33,000	'	30,000	'
Shares used for dilutive computation	47,770,000	41,905,000	45,957,000	41,886,000
Net income per share - basic (in dollars per share)	$0.61	$0.71	$0.91	$1.05
Net income per share - diluted (in dollars per share)	$0.61	$0.71	$0.90	$1.05
Earnings per share calculations	'	'	'	'
Dilutive shares	33,000	'	30,000	'
Stock Appreciation Rights	'	'	'	'
Earnings Per Share Calculations	'	'	'	'
Dilutive shares	'	'	283,856	'
Earnings per share calculations	'	'	'	'
Anti-dilutive shares	'	'	'	283,856
Dilutive shares	'	'	283,856	'

Pension_Plan_and_Other_Postret2

Pension Plan and Other Postretirement Benefits (Details) (USD $)	3 Months Ended		9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Pension Plan and Other Postretirement Benefits	'	'	'	'
Cash payments by the entity related to pension plans and other postretirement benefits	'	'	$28,100,000	$25,500,000
Pension Plan	'	'	'	'
Components of the pension plans and other postretirement benefits	'	'	'	'
Estimated cash contributions in the current fiscal year	'	'	31,100,000	'
Service cost	4,019,000	3,863,000	13,335,000	11,588,000
Interest cost	4,140,000	3,822,000	12,266,000	11,465,000
Expected return on plan assets	-3,559,000	-2,890,000	-10,689,000	-8,669,000
Amortization of prior service cost	1,542,000	1,571,000	4,624,000	4,712,000
Recognized net actuarial loss	2,404,000	2,000,000	6,852,000	6,001,000
Net periodic benefit cost	8,546,000	8,366,000	26,388,000	25,097,000
Other Benefits	'	'	'	'
Components of the pension plans and other postretirement benefits	'	'	'	'
Estimated cash contributions in the current fiscal year	'	'	7,200,000	'
Service cost	1,636,000	1,374,000	5,025,000	4,121,000
Interest cost	1,121,000	986,000	3,339,000	2,958,000
Expected return on plan assets	-600,000	-458,000	-1,796,000	-1,374,000
Recognized net initial APBO	3,000	69,000	7,000	207,000
Amortization of prior service cost	21,000	29,000	61,000	87,000
Recognized net actuarial loss	961,000	793,000	2,794,000	2,379,000
Net periodic benefit cost	$3,142,000	$2,793,000	$9,430,000	$8,378,000

Shortterm_and_Longterm_Borrowi1

Short-term and Long-term Borrowings (Details) (USD $)	9 Months Ended		9 Months Ended						0 Months Ended
In Millions, unless otherwise specified	Sep. 30, 2013	Jun. 29, 2011	Sep. 30, 2013	Sep. 30, 2013	Sep. 30, 2013	Dec. 31, 2012	Sep. 30, 2012	Jun. 29, 2011	Jun. 29, 2011	Sep. 30, 2013	Dec. 31, 2012
			Minimum	Maximum	California Water Service Group	California Water Service Group	California Water Service Group	California Water Service Group	Cal Water	Cal Water	Cal Water
Short-term borrowings	'	'	'	'	'	'	'	'	'	'	'
Maximum borrowing capacity	'	$400	'	'	'	'	'	$100	$300	'	'
Period within which borrowings are to be repaid	'	'	'	'	'	'	'	'	'12 months	'	'
Basis of interest rate	'LIBOR	'	'	'	'	'	'	'	'	'	'
Interest rate margin (as a percent)	'	'	0.73%	0.95%	'	'	'	'	'	'	'
Commitment fee (as a percent)	'	'	0.08%	0.13%	'	'	'	'	'	'	'
Amount outstanding under line of credit	'	'	'	'	$11.50	$64.50	'	'	'	$0	$25
Average borrowing rate (as a percent)	'	'	'	'	2.30%	'	1.70%	'	'	'	'

Income_Taxes_Details

Income Taxes (Details) (USD $)	9 Months Ended	12 Months Ended	0 Months Ended			3 Months Ended	9 Months Ended
In Millions, unless otherwise specified	Sep. 30, 2013	Dec. 31, 2012	Oct. 24, 2013	Dec. 31, 2012	Dec. 31, 2012	Sep. 30, 2013	Sep. 30, 2013
			Federal	Federal	State	State of California	State of California
						State	State
Income taxes	'	'	'	'	'	'	'
Tax credits	'	'	'	'	'	$4.40	'
Tax credit carry-forward period	'	'	'	'	'	'	'10 years
Estimated carried-forward portion of tax credits	'	'	'	'	'	2.3	2.3
Unrecognized tax benefits	'	'	'	'	'	0.6	0.6
Net operating loss resulting from repairs and maintenance deductions	'	'	'	38.8	58.4	'	'
Estimated repairs and maintenance deductions	5	'	'	'	'	'	'
Additional first year bonus depreciation (as a percent)	50.00%	'	'	'	'	'	'
Valuation allowance	'	0	'	'	'	'	'
Federal income tax bonus deduction	10	14.5	'	'	'	'	'
Amount of changes to previously reported taxes	'	'	$0	'	'	'	'

Regulatory_Assets_and_Liabilit1

Regulatory Assets and Liabilities (Details) (USD $)	3 Months Ended					9 Months Ended
	Sep. 30, 2013	Dec. 31, 2012	Dec. 31, 2011	Sep. 30, 2013	Dec. 31, 2012	Sep. 30, 2013	Sep. 30, 2013	Dec. 31, 2012
				Pension costs	Pension costs	Conservation costs	Pension costs	Pension costs
Regulatory Assets and Liabilities	'	'	'	'	'	'	'	'
Portion of litigation proceeds received by Cal Water to replace infrastructure damaged by the gasoline additive Methyl tert-butyl ether (MTBE)	'	'	$34,200,000	'	'	'	'	'
Reclassification from other long-term liabilities to Contributions in Aid of Construction	'	22,400,000	'	'	'	'	'	'
Amount of net proceeds used to replace damaged infrastructure	800,000	'	'	'	'	'	'	'
MTBE regulatory and other liabilities	9,800,000	'	'	'	'	'	'	'
Balancing account disclosures	'	'	'	'	'	'	'	'
Period considered while calculating regulatory liability	'	'	'	'	'	'3 years	'	'
Regulatory assets	'	'	'	'	'	'	2,300,000	2,400,000
Regulatory and other liabilities	'	'	'	$7,700,000	$6,500,000	'	'	'

Commitment_and_Contingencies_D

Commitment and Contingencies (Details) (USD $)	Sep. 30, 2013	Dec. 31, 2012
In Millions, unless otherwise specified
Commitment and Contingencies	'	'
Contingency loss recognized liability	$1.10	$1.10

Fair_Value_of_Financial_Assets2

Fair Value of Financial Assets and Liabilities (Details) (USD $)	9 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2013	Dec. 31, 2012
Fair Value of Financial Assets and Liabilities	'	'
Risk premium (as a percent)	1.19%	'
Advances for construction	$184,879	$187,584
Level 1	'	'
Fair Value of Financial Assets and Liabilities	'	'
Money Market Investment	48,847	'
Total assets	48,847	'
Level 2	'	'
Fair Value of Financial Assets and Liabilities	'	'
Long-term debt, including current maturities	570,058	613,211
Advances for construction	71,242	70,914
Total liabilities	641,300	684,125
Total	'	'
Fair Value of Financial Assets and Liabilities	'	'
Money Market Investment	48,847	'
Total assets	48,847	'
Long-term debt, including current maturities	570,058	613,211
Advances for construction	71,242	70,914
Total liabilities	641,300	684,125
Cost	'	'
Fair Value of Financial Assets and Liabilities	'	'
Money Market Investment	48,847	'
Total assets	48,847	'
Long-term debt, including current maturities	478,240	481,250
Advances for construction	184,879	187,584
Total liabilities	$663,119	$668,834

Condensed_Consolidating_Financ2

Condensed Consolidating Financial Statements (Details) (USD $)	Sep. 30, 2013	Dec. 31, 2012	Sep. 30, 2013	Dec. 31, 2012	Sep. 30, 2013	Apr. 17, 2009	Sep. 30, 2013	Nov. 17, 2010
In Millions, unless otherwise specified	Cal Water	Cal Water	All Other Subsidiaries	All Other Subsidiaries	First Mortgage Bonds, 5.875% due 2019	First Mortgage Bonds, 5.875% due 2019	First Mortgage Bonds, 5.500% due 2040	First Mortgage Bonds, 5.500% due 2040
					Cal Water	Cal Water	Cal Water	Cal Water
Long-term debt	'	'	'	'	'	'	'	'
Debt issued	'	'	'	'	'	$100	'	$100
Interest rate (as a percent)	'	'	'	'	5.88%	'	5.50%	'
Ownership interest (as a percent)	100.00%	100.00%	100.00%	100.00%	'	'	'	'

Condensed_Consolidating_Financ3

Condensed Consolidating Financial Statements (Details 2) (USD $)	Sep. 30, 2013	Dec. 31, 2012	Sep. 30, 2012	Dec. 31, 2011
In Thousands, unless otherwise specified
Utility plant:	'	'	'	'
Utility plant	$2,190,573	$2,096,363	'	'
Less accumulated depreciation and amortization	-685,351	-639,307	'	'
Net utility plant	1,505,222	1,457,056	'	'
Current assets:	'	'	'	'
Cash and cash equivalents	48,847	38,790	16,971	27,203
Receivables and unbilled revenue, net	105,643	91,315	'	'
Other current assets	16,062	16,459	'	'
Total current assets	170,552	146,564	'	'
Other assets:	'	'	'	'
Regulatory assets	354,879	344,419	'	'
Other assets	52,780	47,885	'	'
Total other assets	407,659	392,304	'	'
Total assets	2,083,433	1,995,924	'	'
Capitalization:	'	'	'	'
Common stockholders' equity	600,254	473,712	'	'
Long-term debt, less current maturities	430,227	434,467	'	'
Total capitalization	1,030,481	908,179	'	'
Current liabilities:	'	'	'	'
Current maturities of long-term debt	48,013	46,783	'	'
Short-term borrowings	11,515	89,475	'	'
Accounts payable	60,414	47,199	'	'
Accrued expenses and other liabilities	77,071	59,610	'	'
Total current liabilities	197,013	243,067	'	'
Unamortized investment tax credits	2,180	2,180	'	'
Deferred income taxes, net	168,091	158,846	'	'
Pension and postretirement benefits other than pensions	247,335	244,901	'	'
Regulatory and other liabilities	91,185	92,593	'	'
Advances for construction	184,879	187,584	'	'
Contributions in aid of construction	162,269	158,574	'	'
Total capitalization and liabilities	2,083,433	1,995,924	'	'
Parent Company	'	'	'	'
Utility plant:	'	'	'	'
Utility plant	1,246	606	'	'
Less accumulated depreciation and amortization	-150	-108	'	'
Net utility plant	1,096	498	'	'
Current assets:	'	'	'	'
Cash and cash equivalents	4,272	1,470	1,198	89
Receivables from affiliates	28,964	19,367	'	'
Other current assets	73	'	'	'
Total current assets	33,309	20,837	'	'
Other assets:	'	'	'	'
Investments in affiliates	546,123	492,188	'	'
Long-term affiliate notes receivable	30,252	31,218	'	'
Other assets	1,196	1,023	'	'
Total other assets	577,571	524,429	'	'
Total assets	611,976	545,764	'	'
Capitalization:	'	'	'	'
Common stockholders' equity	600,254	473,712	'	'
Affiliate long-term debt	'	7,781	'	'
Total capitalization	600,254	481,493	'	'
Current liabilities:	'	'	'	'
Short-term borrowings	11,515	64,475	'	'
Payables to affiliates	24	77	'	'
Accrued expenses and other liabilities	762	298	'	'
Total current liabilities	12,301	64,850	'	'
Deferred income taxes, net	-579	-579	'	'
Total capitalization and liabilities	611,976	545,764	'	'
Cal Water	'	'	'	'
Utility plant:	'	'	'	'
Utility plant	2,013,475	1,927,190	'	'
Less accumulated depreciation and amortization	-650,679	-607,992	'	'
Net utility plant	1,362,796	1,319,198	'	'
Current assets:	'	'	'	'
Cash and cash equivalents	42,545	34,609	14,439	18,475
Receivables and unbilled revenue, net	100,810	87,482	'	'
Receivables from affiliates	5,539	3,195	'	'
Other current assets	15,038	15,535	'	'
Total current assets	163,932	140,821	'	'
Other assets:	'	'	'	'
Regulatory assets	352,232	341,877	'	'
Long-term affiliate notes receivable	'	7,781	'	'
Other assets	44,610	40,005	'	'
Total other assets	396,842	389,663	'	'
Total assets	1,923,570	1,849,682	'	'
Capitalization:	'	'	'	'
Common stockholders' equity	500,359	442,923	'	'
Long-term debt, less current maturities	428,878	431,433	'	'
Total capitalization	929,237	874,356	'	'
Current liabilities:	'	'	'	'
Current maturities of long-term debt	46,129	46,104	'	'
Short-term borrowings	'	25,000	'	'
Payables to affiliates	180	1,152	'	'
Accounts payable	57,434	41,352	'	'
Accrued expenses and other liabilities	75,168	58,293	'	'
Total current liabilities	178,911	171,901	'	'
Unamortized investment tax credits	2,180	2,180	'	'
Deferred income taxes, net	164,716	155,481	'	'
Pension and postretirement benefits other than pensions	247,335	244,901	'	'
Regulatory and other liabilities	82,416	83,942	'	'
Advances for construction	184,110	186,753	'	'
Contributions in aid of construction	134,665	130,168	'	'
Total capitalization and liabilities	1,923,570	1,849,682	'	'
All Other Subsidiaries	'	'	'	'
Utility plant:	'	'	'	'
Utility plant	183,049	175,764	'	'
Less accumulated depreciation and amortization	-36,109	-32,710	'	'
Net utility plant	146,940	143,054	'	'
Current assets:	'	'	'	'
Cash and cash equivalents	2,030	2,711	1,334	8,639
Receivables and unbilled revenue, net	4,833	3,833	'	'
Receivables from affiliates	181	1,152	'	'
Other current assets	951	924	'	'
Total current assets	7,995	8,620	'	'
Other assets:	'	'	'	'
Regulatory assets	2,647	2,542	'	'
Other assets	7,179	7,062	'	'
Total other assets	9,826	9,604	'	'
Total assets	164,761	161,278	'	'
Capitalization:	'	'	'	'
Common stockholders' equity	51,271	54,774	'	'
Affiliate long-term debt	30,252	31,218	'	'
Long-term debt, less current maturities	1,349	3,034	'	'
Total capitalization	82,872	89,026	'	'
Current liabilities:	'	'	'	'
Current maturities of long-term debt	1,884	679	'	'
Payables to affiliates	34,480	22,485	'	'
Accounts payable	2,980	5,847	'	'
Accrued expenses and other liabilities	1,059	1,019	'	'
Total current liabilities	40,403	30,030	'	'
Deferred income taxes, net	4,344	4,334	'	'
Regulatory and other liabilities	8,769	8,651	'	'
Advances for construction	769	831	'	'
Contributions in aid of construction	27,604	28,406	'	'
Total capitalization and liabilities	164,761	161,278	'	'
Consolidating Adjustments	'	'	'	'
Utility plant:	'	'	'	'
Utility plant	-7,197	-7,197	'	'
Less accumulated depreciation and amortization	1,587	1,503	'	'
Net utility plant	-5,610	-5,694	'	'
Current assets:	'	'	'	'
Receivables from affiliates	-34,684	-23,714	'	'
Total current assets	-34,684	-23,714	'	'
Other assets:	'	'	'	'
Investments in affiliates	-546,123	-492,188	'	'
Long-term affiliate notes receivable	-30,252	-38,999	'	'
Other assets	-205	-205	'	'
Total other assets	-576,580	-531,392	'	'
Total assets	-616,874	-560,800	'	'
Capitalization:	'	'	'	'
Common stockholders' equity	-551,630	-497,697	'	'
Affiliate long-term debt	-30,252	-38,999	'	'
Total capitalization	-581,882	-536,696	'	'
Current liabilities:	'	'	'	'
Payables to affiliates	-34,684	-23,714	'	'
Accrued expenses and other liabilities	82	'	'	'
Total current liabilities	-34,602	-23,714	'	'
Deferred income taxes, net	-390	-390	'	'
Total capitalization and liabilities	($616,874)	($560,800)	'	'

Condensed_Consolidating_Financ4

Condensed Consolidating Financial Statements (Details 3) (USD $)	3 Months Ended		9 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Condensed Consolidating Financial Statements	'	'	'	'
Operating revenue	$184,404	$178,135	$450,403	$438,436
Operations:	'	'	'	'
Water production costs	70,614	66,489	171,956	158,119
Administrative and general	24,670	23,925	73,106	69,110
Other operations	17,657	17,658	50,332	59,213
Maintenance	4,575	4,377	12,896	14,742
Depreciation and amortization	14,505	13,720	43,625	41,383
Income tax (benefit) expense	11,165	10,387	19,567	19,477
Property and other taxes	5,414	5,218	16,564	13,802
Total operating expenses	148,600	141,774	388,046	375,846
Net operating income	35,804	36,361	62,357	62,590
Other Income and Expenses:	'	'	'	'
Non-regulated revenue	3,649	3,756	10,386	11,943
Non-regulated expense, net	-2,825	-2,697	-8,482	-8,491
Income tax (expense) benefit on other income and expense	-330	-422	-765	-1,383
Net other income	494	637	1,139	2,069
Interest:	'	'	'	'
Interest expense	7,687	8,024	23,527	23,484
Less: capitalized interest	-540	-798	-1,619	-2,647
Net interest expense	7,147	7,226	21,908	20,837
Net income	29,151	29,772	41,588	43,822
Parent Company	'	'	'	'
Operations:	'	'	'	'
Depreciation and amortization	14	'	42	'
Income tax (benefit) expense	-17	-150	-246	-416
Total operating expenses	-3	-150	-204	-416
Net operating income	3	150	204	416
Other Income and Expenses:	'	'	'	'
Non-regulated revenue	572	474	1,739	1,429
Income tax (expense) benefit on other income and expense	-232	-193	-708	-582
Net other income	340	281	1,031	847
Interest:	'	'	'	'
Interest expense	30	368	563	1,022
Net interest expense	30	368	563	1,022
Equity earnings of subsidiaries	28,838	29,709	40,916	43,581
Net income	29,151	29,772	41,588	43,822
Cal Water	'	'	'	'
Condensed Consolidating Financial Statements	'	'	'	'
Operating revenue	174,699	168,680	425,860	413,796
Operations:	'	'	'	'
Water production costs	67,981	63,647	164,524	150,396
Administrative and general	22,354	21,639	65,423	62,043
Other operations	15,883	16,177	45,490	54,584
Maintenance	4,382	4,238	12,376	14,247
Depreciation and amortization	13,714	13,051	41,168	39,393
Income tax (benefit) expense	10,721	9,831	19,807	19,094
Property and other taxes	4,680	4,552	14,549	11,819
Total operating expenses	139,715	133,135	363,337	351,576
Net operating income	34,984	35,545	62,523	62,220
Other Income and Expenses:	'	'	'	'
Non-regulated revenue	3,385	3,372	9,572	10,867
Non-regulated expense, net	-2,515	-2,217	-7,308	-7,072
Income tax (expense) benefit on other income and expense	-355	-469	-923	-1,545
Net other income	515	686	1,341	2,250
Interest:	'	'	'	'
Interest expense	7,608	7,702	22,966	22,648
Less: capitalized interest	-495	-505	-1,279	-1,785
Net interest expense	7,113	7,197	21,687	20,863
Net income	28,386	29,034	42,177	43,607
All Other Subsidiaries	'	'	'	'
Condensed Consolidating Financial Statements	'	'	'	'
Operating revenue	9,705	9,455	24,543	24,640
Operations:	'	'	'	'
Water production costs	2,633	2,842	7,432	7,723
Administrative and general	2,316	2,286	7,683	7,067
Other operations	1,900	1,607	5,220	5,008
Maintenance	193	139	520	495
Depreciation and amortization	805	699	2,499	2,079
Income tax (benefit) expense	107	372	-1,064	-198
Property and other taxes	734	666	2,015	1,983
Total operating expenses	8,688	8,611	24,305	24,157
Net operating income	1,017	844	238	483
Other Income and Expenses:	'	'	'	'
Non-regulated revenue	475	617	1,415	1,805
Non-regulated expense, net	-310	-483	-1,174	-1,422
Income tax (expense) benefit on other income and expense	-85	-82	-169	-216
Net other income	80	52	72	167
Interest:	'	'	'	'
Interest expense	707	535	1,961	1,594
Less: capitalized interest	-45	-293	-340	-862
Net interest expense	662	242	1,621	732
Net income	435	654	-1,311	-82
Consolidating Adjustments	'	'	'	'
Operations:	'	'	'	'
Other operations	-126	-126	-378	-379
Depreciation and amortization	-28	-30	-84	-89
Income tax (benefit) expense	354	334	1,070	997
Total operating expenses	200	178	608	529
Net operating income	-200	-178	-608	-529
Other Income and Expenses:	'	'	'	'
Non-regulated revenue	-783	-707	-2,340	-2,158
Non-regulated expense, net	'	3	'	3
Income tax (expense) benefit on other income and expense	342	322	1,035	960
Net other income	-441	-382	-1,305	-1,195
Interest:	'	'	'	'
Interest expense	-658	-581	-1,963	-1,780
Net interest expense	-658	-581	-1,963	-1,780
Equity earnings of subsidiaries	-28,838	-29,709	-40,916	-43,581
Net income	($28,821)	($29,688)	($40,866)	($43,525)

Condensed_Consolidating_Financ5

Condensed Consolidating Financial Statements (Details 4) (USD $)	3 Months Ended		9 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Operating activities:	'	'	'	'
Net income (loss)	$29,151	$29,772	$41,588	$43,822
Adjustments to reconcile net income (loss) to net cash provided by (used in) operating activities:	'	'	'	'
Depreciation and amortization	'	'	45,067	42,722
Change in value of life insurance contracts	'	'	-1,147	-2,244
Other changes in noncurrent assets and liabilities	'	'	13,501	28,411
Changes in operating assets and liabilities	'	'	2,890	-13,306
Net cash provided by operating activities	'	'	101,899	99,405
Investing activities:	'	'	'	'
Utility plant expenditures	'	'	-94,782	-99,600
Purchase of life insurance	'	'	-3,204	-3,199
Restricted cash and other changes, net	'	'	1,148	1,553
Net cash (used in) investing activities	'	'	-96,838	-101,246
Financing Activities:	'	'	'	'
Short-term borrowings	'	'	35,315	65,565
Repayment of short-term borrowings	'	'	-113,275	-52,030
Proceeds from long-term debt	'	'	48	123
Repayment of long-term debt	'	'	-3,058	-2,123
Advances and contributions in aid for construction	'	'	7,577	5,491
Refunds of advances for construction	'	'	-5,230	-5,632
Dividends paid to non-affiliates	'	'	-21,981	-19,785
Issuance of common stock	'	'	105,600	'
Issuance of common stock	'	'	110,688	'
Net cash provided by (used in) financing activities	'	'	4,996	-8,391
Change in cash and cash equivalents	'	'	10,057	-10,232
Cash and cash equivalents at beginning of period	'	'	38,790	27,203
Cash and cash equivalents at end of period	48,847	16,971	48,847	16,971
Parent Company	'	'	'	'
Operating activities:	'	'	'	'
Net income (loss)	29,151	29,772	41,588	43,822
Adjustments to reconcile net income (loss) to net cash provided by (used in) operating activities:	'	'	'	'
Equity earnings of subsidiaries	-28,838	-29,709	-40,916	-43,581
Dividends received from affiliates	'	'	21,981	19,785
Depreciation and amortization	'	'	42	'
Other changes in noncurrent assets and liabilities	'	'	1,164	1,180
Changes in operating assets and liabilities	'	'	390	-247
Net cash provided by operating activities	'	'	24,249	20,959
Investing activities:	'	'	'	'
Utility plant expenditures	'	'	-640	'
Investment in affiliates	'	'	-35,000	'
Net changes in affiliate advances	'	'	-9,583	-13,975
Repayment of affiliates long-term debt	'	'	913	411
Net cash (used in) investing activities	'	'	-44,310	-13,564
Financing Activities:	'	'	'	'
Short-term borrowings	'	'	15,315	14,535
Repayment of short-term borrowings	'	'	-68,275	-1,000
Repayment of affiliates long-term debt	'	'	-7,796	-36
Dividends paid to non-affiliates	'	'	-21,981	-19,785
Issuance of common stock	'	'	105,600	'
Net cash provided by (used in) financing activities	'	'	22,863	-6,286
Change in cash and cash equivalents	'	'	2,802	1,109
Cash and cash equivalents at beginning of period	'	'	1,470	89
Cash and cash equivalents at end of period	4,272	1,198	4,272	1,198
Cal Water	'	'	'	'
Operating activities:	'	'	'	'
Net income (loss)	28,386	29,034	42,177	43,607
Adjustments to reconcile net income (loss) to net cash provided by (used in) operating activities:	'	'	'	'
Depreciation and amortization	'	'	42,509	40,604
Change in value of life insurance contracts	'	'	-1,147	-2,244
Other changes in noncurrent assets and liabilities	'	'	12,415	30,928
Changes in operating assets and liabilities	'	'	4,220	-10,557
Net cash provided by operating activities	'	'	100,174	102,338
Investing activities:	'	'	'	'
Utility plant expenditures	'	'	-84,688	-88,593
Net changes in affiliate advances	'	'	-2,359	2,708
Repayment of affiliates long-term debt	'	'	7,797	36
Purchase of life insurance	'	'	-3,204	-3,199
Restricted cash and other changes, net	'	'	1,148	1,553
Net cash (used in) investing activities	'	'	-81,306	-87,495
Financing Activities:	'	'	'	'
Short-term borrowings	'	'	20,000	51,030
Repayment of short-term borrowings	'	'	-45,000	-51,030
Repayment of long-term debt	'	'	-2,531	-1,573
Net changes in affiliate advances	'	'	-972	524
Advances and contributions in aid for construction	'	'	7,545	5,416
Refunds of advances for construction	'	'	-5,184	-5,575
Dividends paid to affiliates	'	'	-19,790	-17,671
Investment from affiliates	'	'	35,000	'
Net cash provided by (used in) financing activities	'	'	-10,932	-18,879
Change in cash and cash equivalents	'	'	7,936	-4,036
Cash and cash equivalents at beginning of period	'	'	34,609	18,475
Cash and cash equivalents at end of period	42,545	14,439	42,545	14,439
All Other Subsidiaries	'	'	'	'
Operating activities:	'	'	'	'
Net income (loss)	435	654	-1,311	-82
Adjustments to reconcile net income (loss) to net cash provided by (used in) operating activities:	'	'	'	'
Depreciation and amortization	'	'	2,600	2,207
Other changes in noncurrent assets and liabilities	'	'	-29	-3,815
Changes in operating assets and liabilities	'	'	-1,803	-2,417
Net cash provided by operating activities	'	'	-543	-4,107
Investing activities:	'	'	'	'
Utility plant expenditures	'	'	-9,454	-11,007
Net changes in affiliate advances	'	'	1,141	'
Net cash (used in) investing activities	'	'	-8,313	-11,007
Financing Activities:	'	'	'	'
Proceeds from long-term debt	'	'	48	123
Repayment of long-term debt	'	'	-527	-550
Net changes in affiliate advances	'	'	11,773	10,743
Repayment of affiliates long-term debt	'	'	-914	-411
Advances and contributions in aid for construction	'	'	32	75
Refunds of advances for construction	'	'	-46	-57
Dividends paid to affiliates	'	'	-2,191	-2,114
Net cash provided by (used in) financing activities	'	'	8,175	7,809
Change in cash and cash equivalents	'	'	-681	-7,305
Cash and cash equivalents at beginning of period	'	'	2,711	8,639
Cash and cash equivalents at end of period	2,030	1,334	2,030	1,334
Consolidating Adjustments	'	'	'	'
Operating activities:	'	'	'	'
Net income (loss)	-28,821	-29,688	-40,866	-43,525
Adjustments to reconcile net income (loss) to net cash provided by (used in) operating activities:	'	'	'	'
Equity earnings of subsidiaries	28,838	29,709	40,916	43,581
Dividends received from affiliates	'	'	-21,981	-19,785
Depreciation and amortization	'	'	-84	-89
Other changes in noncurrent assets and liabilities	'	'	-49	118
Changes in operating assets and liabilities	'	'	83	-85
Net cash provided by operating activities	'	'	-21,981	-19,785
Investing activities:	'	'	'	'
Investment in affiliates	'	'	35,000	'
Net changes in affiliate advances	'	'	10,801	11,267
Repayment of affiliates long-term debt	'	'	-8,710	-447
Net cash (used in) investing activities	'	'	37,091	10,820
Financing Activities:	'	'	'	'
Net changes in affiliate advances	'	'	-10,801	-11,267
Repayment of affiliates long-term debt	'	'	8,710	447
Dividends paid to affiliates	'	'	21,981	19,785
Investment from affiliates	'	'	-35,000	'
Net cash provided by (used in) financing activities	'	'	($15,110)	$8,965