| Organization, Consolidation and Presentation of Financial Statements Disclosure [Text Block] | 1. Basis of Preparation of Financials The condensed consolidated financial statements included herein have been prepared by Connecticut Water Service, Inc. (the “Company”) and its wholly-owned subsidiaries, pursuant to the rules and regulations of the Securities and Exchange Commission and reflect all adjustments that are of a normal recurring nature which are, in the opinion of management, necessary to a fair statement of the results for interim periods. Certain information and footnote disclosures have been omitted pursuant to such rules and regulations, although the Company believes that the disclosures are adequate to make the information presented not misleading. The Company’s primary operating subsidiaries are: The Connecticut Water Company (“Connecticut Water”) and The Maine Water Company (“Maine Water”). The Condensed Consolidated Balance Sheet at December 31, 2015 has been derived from the audited financial statements at that date but does not include all of the information and footnotes required by accounting principles generally accepted in the United States of America for complete financial statements. It is suggested that these condensed consolidated financial statements be read in conjunction with the financial statements and the notes thereto included in the Company’s latest Annual Report on Form 10-K for the year ended December 31, 2015 (the “10-K”) and as updated in the Company’s Quarterly Report on Forms 10-Q for the periods ending March 31, 2016 and June 30, 2016. The results for interim periods are not necessarily indicative of results to be expected for the year since the consolidated earnings are subject to seasonal factors. During the preparation of the Condensed Consolidated Financial Statements for the quarter ended June 30, 2016, the Company identified two errors related to the accounting treatment of stock-based performance awards granted to officers of the Company. First, the Company had mistakenly classified all stock-based performance awards as equity awards and, secondly, incorrectly marked those awards to the market price of the Company’s common stock price at the end of each reporting period. A portion of these awards should have been classified as liability awards and only those awards should have been marked-to-market based on the Company’s common stock price. During the second quarter of 2016, the Company reversed all of the incorrectly recorded mark-to-market expense as a cumulative out-of-period adjustment resulting in a one-time benefit of approximately $2.6 million on the Operation and Maintenance line item on its Condensed Consolidated Statements of Income for the three months ended June 30, 2016 and $1.6 million for the six months ended June 30, 2016. Approximately $1.6 million of the out of period adjustment pertained to years prior to 2016, with the remaining $1.0 million related to the first quarter of 2016. Additionally, the Company decreased its Common Stock Without Par Value and increased its Long-Term Compensation Arrangement line items on the Condensed Consolidated Balance Sheet as of June 30, 2016 by approximately $0.6 million to reflect both the awards that should have been classified as liability awards and their corresponding mark-to-market adjustments. The Company performed various quantitative and qualitative analyses and determined that these errors were not material to the previously reported quarterly and annual results. The Company also determined that recording these entries as an out-of- period adjustment during the second quarter of 2016 is not expected to be material to the projected results for the full year ended December 31, 2016. Certain previously reported information has been reclassified to conform to the current period presentation. Regulatory Matters The rates we charge our water customers in Connecticut and Maine are established under the jurisdiction of and are approved by the Connecticut Public Utilities Regulatory Authority (“PURA”) and the Maine Public Utilities Commission (“MPUC”), respectively. It is our policy to seek rate relief as necessary to enable us to achieve an adequate rate of return. Connecticut Water’s allowed return on equity and return on rate base, effective September 30, 2016 , were 9.75% and 7.32% , respectively. Maine Water’s average allowed return on equity and return on rate base, effective September 30, 2016 , were 9.50% and 7.96% , respectively. The PURA establishes rates in Connecticut on a company-wide basis while the MPUC approves Maine Water’s rates on a division-by-division basis. Both Connecticut Water and Maine Water are allowed to add surcharges to customers’ bills in order to recover certain approved capital projects in between full rate cases, as well as approved surcharges for Water Revenue Adjustments, as discussed in more detail below, in Connecticut. Heritage Village Water Company Acquisition On May 10, 2016, the Company entered into an Agreement and Plan of Merger (the “HVWC Agreement”) with Heritage Village Water Company, a specially-chartered Connecticut corporation (“HVWC”). Founded in 1969, HVWC is based in Southbury, Connecticut, and serves approximately 4,700 water and 3,000 waste water customers in the southern Connecticut communities of Southbury, Middlebury and Oxford. The Boards of Directors of the Company and HVWC have each unanimously approved the HVWC Agreement. Consummation of the merger is subject to regulatory, HVWC shareholder and other specified approvals described below and is expected to be completed during either the fourth quarter of 2016 or the first quarter of 2017. Under the terms of the HVWC Agreement, each share of HVWC common stock issued and outstanding at the time of the closing of the Merger will be exchanged and converted into the right to receive 240 shares of the common stock of the Company, without par value (the “Company Common Stock”), provided that the Company’s Share Price (as defined below) over a specified period prior to the closing date of the Merger is equal to or greater than $39.45 but less than or equal to $41.45. If the Company’s Share Price is less than $39.45 as of the closing date, each share of HVWC common stock issued and outstanding at the time of the closing of the Merger will be exchanged and converted into the right to receive that number of shares of Company Common Stock equal to $9,468 divided by the Company’s Share Price. If the the Company’s Share Price is more than $41.45 as of the closing date, each share of HVWC common stock issued and outstanding at the time of the closing of the Merger will be exchanged and converted into the right to receive that number of shares of the Company’s Common Stock equal to $9,948 divided by the Company’s Share Price. The “Company’s Share Price” is determined by calculating an average of the closing prices for shares of the Company’s Common Stock on the Nasdaq Stock Market, LLC for the twenty trading days immediately preceding the third business day prior to the closing of the Merger. Holders of HVWC common stock prior to the Merger will receive cash in lieu of fractional shares of Company Common Stock. The HVWC Agreement contains customary representations and warranties regarding, on the one hand, HVWC, its business and operations and related matters, and, on the other hand, the Company, made by the parties as of specified dates, and customary affirmative and negative covenants with respect to the conduct of HVWC’s business prior to the closing. In the HVWC Agreement, HVWC has agreed that its Board of Directors will, subject to certain exceptions, recommend adoption of the HVWC Agreement by HVWC shareholders and the transactions contemplated by the HVWC Agreement. HVWC has also agreed: (i) to cause a special meeting of shareholders of HVWC to be held to consider the approval and adoption of the HVWC Agreement and the transactions contemplated thereby; and (ii) not to solicit proposals relating to alternative business combination transactions or, subject to certain exceptions, enter into discussions concerning confidential information in connection with alternative business combination transactions. The obligation of the parties to complete the Merger is subject to the satisfaction or waiver on or prior to the closing date of certain specified conditions, including the following: (i) receipt of a final and non-appealable order of PURA approving the Merger in form and substance reasonably acceptable to the parties; (ii) approval of the Merger by the affirmative vote of the holders of not less than two-thirds (66 2/3rd%) of HVWC’s issued and outstanding shares of common stock as required under the Connecticut Business Corporation Act (“CBCA”) and by a super-majority vote of ninety (90%) percent of HVWC’s issued and outstanding shares; (iii) the completion of certain specified corporate governance steps regarding HVWC’s Board of Directors, including the appointment of up to three additional directors; (iv) the receipt of all other necessary consents or approvals to the Merger; (v) approval for listing of the Company Common Stock to be issued in the Merger on the Nasdaq Stock Market, LLC; (vi) the absence of laws, orders, judgments and injunctions that restrain, enjoin or otherwise prohibit consummation of the Merger; (vii) effectiveness under the Securities Act of 1933 (the “Securities Act”) of the Company’s registration statement on Form S-4 relating to the issuance of the Company Common Stock in the Merger and absence of any stop order in respect thereof or proceedings by the Securities and Exchange Commission (“SEC”) for that purpose; (viii) the receipt of customary tax opinions from counsel to HVWC and the Company that will state that the Merger will qualify as a tax-free reorganization within the meaning of Section 368(a) of the Internal Revenue Code of 1986; (ix) the accuracy of representations and warranties with respect to the businesses of HVWC and the Company and compliance by HVWC and the Company with their respective covenants contained in the HVWC Agreement; (x) no event(s) occurring that could reasonably be expected to result in a “Company Material Adverse Effect” (as defined in the HVWC Agreement) and (xi) holders of no more than 5% of HVWC’s common stock have exercised appraisal rights under Connecticut law. The parties’ obligation to complete the Merger is also subject to a closing condition related to HVWC’s enabling legislation adopted in 1969. The special act of the Connecticut legislature that formed HVWC provides a right of first refusal (“ROFR”) to the Town of Southbury, Connecticut to purchase HVWC on the same terms and conditions as those set forth in the HVWC Agreement. The Town has a statutory period of ninety (90) days following receipt of notice from HVWC to exercise its right to purchase HVWC on such same terms and conditions. This notice was delivered to the Town on May 10, 2016. On July 28, 2016, the Town of Southbury filed a lawsuit against HVWC and Connecticut Water in Connecticut state court seeking an injunction to preclude the parties from completing the merger or taking other actions that the Town believes will prevent the Town from fully enforcing its ROFR rights. On August 5, 2016, a hearing was held in Waterbury Superior Court at which the Court ordered that the Town’s ROFR deadline be extended to November 14, 2016. The Court’s order allows the Company to continue the approval process, with both state utility regulators and the SEC. The HVWC Agreement contains certain termination rights for both the Company and HVWC and further provides that, in connection with the termination of the HVWC Agreement under specified circumstances, HVWC may be required to pay to the Company, or the Company may be required to pay to HVWC, a termination fee of $100,000 in cash, as liquidated damages. On July 7, 2016, Connecticut Water filed an application with PURA seeking approval of the acquisition. PURA has issued interrogatories, to which the Company has responded, and held public hearings. Based on PURA’s schedule, the Company expects a decision t be rendered by PURA in December 2016. Avon Water Company Acquisition On October 11, 2016, the Company entered into an Agreement and Plan of Merger (the “Avon Agreement”) with The Avon Water Company, a specially-chartered Connecticut corporation (“Avon Water”). Founded in 1911, Avon Water serves about 4,800 customers in the Farmington Valley communities of Avon, Farmington, and Simsbury, Connecticut, and is located near Connecticut Water’s existing operations in Avon and Farmington. The Boards of Directors of the Company and Avon Water have each unanimously approved the Avon Agreement and the transactions contemplated thereby. Consummation of the merger is subject to regulatory, Avon Water shareholder and other specified approvals described below and is expected to be consummated by the end of the first quarter of 2017. Under the terms of the Avon Agreement, each of the 121,989 Avon Water common stock shares outstanding at the time of the closing of the merger will be exchanged and converted into the right to receive the following merger consideration: (i) a cash payment of $50.37; and (ii) a stock consideration component, consisting of 4.38 Company Common Stock, provided that the Company’s Share Price (as defined above) over a specified period prior to the closing date of the merger is equal to or greater than $45.00 but less than or equal to $52.00. If the Company’s Share Price is less than $45.00 as of the closing date, each share of Avon Water common stock issued and outstanding at the time of the closing of the merger will be exchanged and converted into the right to receive that number of shares of Company Common Stock equal to 197.10 divided by the Company’s Share Price, rounded to the nearest hundredth. If the Company’s Share Price is more than $52.00 as of the closing date, each share of Avon Water common stock issued and outstanding at the time of the closing of the merger will be exchanged and converted into the right to receive that number of shares of Company Common Stock equal to 227.76 divided by the Company’s Share Price, rounded to the nearest hundredth. Holders of Avon Water common stock prior to the Merger will receive cash in lieu of fractional shares of Company Common Stock. The Avon Agreement contains customary representations and warranties regarding, on the one hand, Avon Water, its business and operations and related matters, and, on the other hand, the Company, made by the parties as of specified dates, and customary affirmative and negative covenants with respect to the conduct of Avon Water’s business prior to the closing. In the Avon Agreement, Avon Water has agreed that its Board of Directors will, subject to certain exceptions, recommend adoption of the Avon Agreement by Avon Water shareholders and the transactions contemplated by the Avon Agreement. Avon Water has also agreed: (i) to cause a special meeting of shareholders of Avon Water to be held to consider the approval and adoption of the Agreement and the transactions contemplated thereby; and (ii) not to solicit proposals relating to alternative business combination transactions or, subject to certain exceptions, enter into discussions concerning confidential information in connection with alternative business combination transactions. The obligation of the parties to complete the merger is subject to the satisfaction or waiver on or prior to the closing date of certain specified conditions, including the following: (i) receipt of a final and non-appealable order of PURA approving the merger in form and substance reasonably acceptable to the parties; (ii) approval of the merger by the affirmative vote of the holders of not less than two-thirds (66 2/3 rd %) Avon Water’s issued and outstanding shares of common stock as required under the CBCA; (iii) the receipt of all other necessary consents or approvals to the merger; (iv) approval for listing of the Company Common Stock to be issued in the merger on the Nasdaq Stock Market, LLC; (v) the absence of laws, orders, judgments and injunctions that restrain, enjoin or otherwise prohibit consummation of the Merger; (vi) effectiveness under the Securities Act of the Company’s registration statement on Form S-4 relating to the issuance of the Company Common Stock in the merger and absence of any stop order in respect thereof or proceedings by the SEC for that purpose; (vii) the receipt of a legal opinion from counsel to Avon Water regarding certain corporate law matters; (viii) the receipt of a customary tax opinion from counsel to the Company that will state that the merger will qualify as a tax-free reorganization within the meaning of Section 368(a) of the Internal Revenue Code of 1986; (ix) the accuracy of representations and warranties with respect to the businesses of Avon Water and the Company and compliance by Avon Water and the Company with their respective covenants contained in the Avon Agreement; (xi) no event(s) occurring that could reasonably be expected to result in either a “Company Material Adverse Effect” or a “CWS Material Adverse Effect” (each, as defined in the Avon Agreement) and (xii) holders of no more than 5% of Avon Water’s common stock have exercised appraisal rights under Connecticut law. The Avon Agreement contains certain termination rights for both the Company and Avon Water and further provides that, in connection with the termination of the Avon Agreement under specified circumstances, Avon Water may be required to pay to the Company, or the Company may be required to pay to Avon Water, a termination fee of $200,000 in cash, as liquidated damages. During the fourth quarter of 2016, Connecticut Water expects to file an application with PURA seeking approval of the transaction. Maine Water Land Sale On March 11, 2016, Maine Water entered into a purchase and sale agreement with the Coastal Mountains Land Trust, a Maine nonprofit corporation (the “Land Trust”) pursuant to which Maine Water agreed to sell two conservation easements to the Land Trust on approximately 1,300 acres of land located in the towns of Rockport, Camden and Hope, in Knox County, Maine valued in the aggregate at $3.1 million. The land had a book value of approximately $600,000 at December 31, 2015 and is included in “Utility Plant” on the Company’s “Consolidated Balance Sheets”. The easements and purchase prices are as follows: 1. Ragged Mountain Mirror Lake Conservation Easement: $1,875,000; and 2. Grassy Pond conservation Easement: $600,000. The two easement sale and donation transactions are expected to close no later than December 31, 2017 and December 31, 2019, respectively. Maine Water will make a $200,000 contribution to the Land Trust upon completion of the closing of the first easement sale. Maine Water also expects to claim a charitable deduction for the $600,000 in excess of the fair market value of the second easement over the $600,000 sale price. Connecticut Rates In Connecticut, the Water Infrastructure Conservation Adjustment (“WICA”) was 3.04% and 5.12% at September 30, 2015 and 2016 , respectively. On July 27, 2016, Connecticut Water filed a WICA application with the PURA requesting a 2.01% surcharge to customers’ bills, representing approximately $12.8 million in WICA related projects. On September 21, 2016, PURA approved the application as filed, effective October 1, 2016, the Company’s cumulative WICA surcharge was 7.13%. WICA surcharges are capped at 10% between general rate cases. Since 2013, Connecticut law has authorized a Water Revenue Adjustment (“WRA”) to reconcile actual water demands with the demands projected in the last general rate case and allows companies to adjust rates as necessary to recover the revenues approved by PURA in the last general rate case. The WRA removes the financial disincentive for water utilities to develop and implement effective water conservation programs. The WRA allows water companies to defer on the balance sheet, as a regulatory asset or liability, for later collection from or crediting to customers the amount by which actual revenues deviate from the revenues allowed in the most recent general rate proceedings, including WICA proceedings. Additionally, projects eligible for WICA surcharges were expanded to include energy conservation projects, improvements required to comply with streamflow regulations, and improvements to acquired systems. Connecticut Water’s allowed revenues for the nine months ended September 30, 2016 , as approved by PURA during our 2010 general rate case and including subsequently approved WICA surcharges, are approximately $59.1 million. Through normal billing for the nine months ended September 30, 2016 , revenue for Connecticut Water would have been approximately $56.2 million had the WRA not been implemented. As a result of the implementation of the WRA, Connecticut Water recorded $2.9 million in additional revenue for the nine months ended September 30, 2016 . Maine Rates In Maine, the overall, cumulative Water Infrastructure Charge (“WISC”) for all divisions was 1.13% and 4.08% as of September 30, 2015 and 2016, respectively. In 2014 and 2015, Maine Water petitioned the MPUC for approval of accounting orders that would address (1) the return to its customers a federal income tax refund stemming from the adoption of the Internal Revenue Service (“IRS”) Revenue Procedure 2012-19 (“Repair Regulations”), and (2) the treatment of any benefit resulting from the elimination of deferred tax liabilities previously recorded on these qualifying fixed assets that are now deducted under the Repair Regulations. On February 26, 2015, the MPUC approved a stipulation between Maine Water and the Office of the Public Advocate that refunds $2.9 million to the customers of the eight divisions over a two-year period starting no later than July 1, 2015, and allows the flow-through treatment of the repair deduction as of January 1, 2014. In addition, Maine Water agreed not to file a general rate case during the two-year refund period in any of the eight divisions that were allowed the refund. On June 22, 2015, the MPUC approved a settlement agreement between Maine Water and the Office of the Public Advocate that allowed for the amortization of the deferred tax liabilities over a one to nine year period, depending on the division. Maine Water commenced amortization per the agreed upon schedule. With the completion of these two dockets, Maine Water recorded in the quarter ended June 30, 2015 the retroactive benefit associated with the flow-through of the Repair Regulations from January 1, 2014. The 2014 benefit, reflected in the second quarter of 2015, was approximately $931,000, or $0.09 per basic share outstanding. A newly passed water revenue adjustment mechanism law in Maine became available to regulated water utilities in Maine on October 15, 2015. Maine Water is currently precluded from seeking new rates due to various agreements with the MPUC, but is evaluating how and when this new mechanism can be implemented. |
