Proposed Merger	6 Months Ended
Jun. 30, 2016
Business Combinations [Abstract]
Proposed Merger	Termination of proposed merger and other matters On December 3, 2014, HEI, NextEra Energy, Inc., a Florida corporation (NEE), NEE Acquisition Sub I, LLC, a Delaware limited liability company and a wholly owned subsidiary of NEE (Merger Sub II) and NEE Acquisition Sub II, Inc., a Delaware corporation and a wholly owned subsidiary of NEE (Merger Sub I), entered into an Agreement and Plan of Merger (the Merger Agreement). The Merger Agreement provided for Merger Sub I to merge with and into HEI (the Initial Merger), with HEI surviving, and then for HEI to merge with and into Merger Sub II, with Merger Sub II surviving as a wholly owned subsidiary of NEE (the Merger). The Merger Agreement contemplated that, immediately prior to the closing of the Merger, HEI would distribute to its shareholders all of the issued and outstanding shares of common stock of ASB Hawaii, Inc. (ASB Hawaii), the direct parent company of ASB (such distribution referred to as the Spin-Off), with ASB Hawaii becoming a new public company. The closing of the Merger was subject to various conditions, including, among others, receipt of regulatory approval from the Hawaii Public Utilities Commission (PUC). In January 2015, NEE and Hawaiian Electric filed an application with the PUC requesting approval of the proposed Merger (under which Hawaiian Electric would become a wholly-owned indirect subsidiary of NEE). On July 15, 2016, the PUC dismissed the application without prejudice. On July 16, 2016, pursuant to the terms of the Merger Agreement, NEE provided written notice to HEI indicating that NEE was terminating the Merger Agreement effective immediately. Pursuant to the terms of the Merger Agreement, on July 19, 2016, NEE paid HEI a $90 million termination fee and $5 million for the reimbursement of expenses associated with the transaction. In the third quarter of 2016, HEI will recognize for financial reporting purposes the termination fee and reimbursement of expenses (net of taxes), additional tax benefits of approximately $7.8 million on the previously non-tax-deductible merger- and spin-off-related expenses incurred through June 30, 2016, and merger- and spin-off-related expenses incurred in the third quarter of 2016 (net of tax benefits). The Spin-Off of ASB Hawaii was cancelled as it was cross-conditioned on the merger consummation. On May 18, 2016, the Utilities filed an application for an LNG supply and transport agreement and LNG-related capital equipment to utilize natural gas at certain designated facilities, and two applications to commit funds for and waive from the PUC’s Framework for Competitive Bidding the Kahe Combined Cycle Generating Unit project. The three filings were conditioned on PUC approval of the Utilities’ and NextEra Energy’s joint application for approval of a merger between the two parties. On July 19, 2016, the Utilities filed withdrawals of these three applications, noting that because the merger application approval condition was not satisfied, the underlying projects would not go forward. On July 21, 2016, the PUC issued orders closing all three dockets. Litigation. HEI and its subsidiaries are subject to various legal proceedings that arise from time to time. Some of these proceedings may seek relief or damages in amounts that may be substantial. Because these proceedings are complex, many years may pass before they are resolved, and it is not feasible to predict their outcomes. Some of these proceedings involve claims HEI and Hawaiian Electric believe may be covered by insurance, and HEI and Hawaiian Electric have advised their insurance carriers accordingly. Since the December 3, 2014 announcement of the merger agreement, eight purported class action complaints were filed in the Circuit Court of the First Circuit for the State of Hawaii by alleged stockholders of HEI against HEI, Hawaiian Electric (in one complaint), the individual directors of HEI, NEE and NEE's acquisition subsidiaries. The lawsuits are captioned as follows: Miller v. Hawaiian Electric Industries, Inc., et al., Case No. 14-1-2531-12 KTN (December 15, 2014) (the Miller Action); Walsh v. Hawaiian Electric Industries, Inc., et al., Case No. 14-1-2541-12 JHC (December 15, 2014) (the Walsh Action); Stein v. Hawaiian Electric Industries, Inc., et al., Case No. 14-1-2555-12 KTN (December 17, 2014) (the Stein Action); Brown v. Hawaiian Electric Industries, Inc., et al., Case No. 14-1-2643-12 RAN (December 30, 2014) (the Brown Action); Cohn v. Hawaiian Electric Industries, Inc., et al., Case No. 14-1-2642-12 KTN (December 30, 2014) (the Cohn State Action); Guenther v. Watanabe, et al., Case No. 15-1-003-01 ECN (January 2, 2015) (the Guenther Action); Hudson v. Hawaiian Electric Industries, Inc., et al., Case No. 15-1-0013-01 JHC (January 5, 2015) (the Hudson Action); Grieco v. Hawaiian Electric Industries, Inc., et al., Case No. 15-1-0094-01 KKS (January 21, 2015) (the Grieco Action). On January 12, 2015, plaintiffs in the Miller Action, the Walsh Action, the Stein Action, the Brown Action, the Guenther Action, and the Hudson Action filed a motion to consolidate their actions and to appoint co-lead counsel. On January 23, 2015, the Cohn State Action was voluntarily dismissed. On January 27, 2015, Cohn filed a purported class action captioned Cohn v. Hawaiian Electric Industries, Inc., et al., Civil No. 15-00029-JMS-RLP in the United States District Court for the District of Hawaii against HEI, the individual directors of HEI, NEE and NEE’s acquisition subsidiaries (the Cohn Federal Action). On February 13, 2015, the state court orally granted the plaintiffs’ motions to consolidate the seven state court actions and appoint co-lead counsel and entered a written order granting the motions on March 6, 2015. On March 10, 2015, plaintiffs filed a first consolidated complaint in state court that added as a defendant J.P. Morgan Securities, LLC (JP Morgan), the financial advisor to HEI for the Merger, and deleted Hawaiian Electric Company, Inc. as a defendant and concurrently served a first request for production of documents on HEI and the individual directors. On March 17, 2015, plaintiffs filed a motion for limited expedited discovery in the consolidated state action and thereafter on March 25, 2015 withdrew their request for limited discovery and first request for production of documents as a result of the parties’ agreement to conduct certain specified limited discovery which included a stipulated confidentiality agreement and protective order protecting the confidentiality of certain information exchanged between the parties in connection with discovery in the consolidated action that was filed on April 6, 2015. On April 15 and 17, 2015, a deposition of a representative of HEI and a representative of JP Morgan were taken, respectively. On April 21, 2015, plaintiffs confirmed the cancellation of the preliminary injunction hearing that had been scheduled for May 5, 2015 in the consolidated action and on April 23, 2015, the state court entered a stipulation and order to extend indefinitely the time to answer or otherwise respond to the first amended consolidated complaint. On April 30, 2015, the state court entered a consolidated case management order confirming the consolidated treatment of the state actions for purposes of case management, pretrial discovery, procedural and other matters. On May 27, 2015, the federal court entered a stipulation and order approving the stipulation of the parties to stay the Cohn Federal Action pending the resolution of the state court consolidated action and administratively closing the Cohn Federal Action without prejudice to any party. On May 29, 2015, the state court entered a stipulated order amending the consolidated caption to read IN RE Consolidated HEI Shareholder Cases, Master File No. Civil No. 1CC15-1-HEI, to add JP Morgan as a named defendant in each individual action, add the caption for the Grieco Action, and remove Hawaiian Electric Company, Inc. from the caption in the Brown Action. In October 2015, several depositions of HEI representatives were taken in the state consolidated action. On February 9, 2016, plaintiffs filed an ex parte motion for second extension of time to file the pretrial statement in the state consolidated action from February 15, 2016 to August 15, 2016. Following the termination of the Merger Agreement, a stipulation and order for dismissal with prejudice of all claims and parties was entered by the court in the Cohn Federal Action on July 22, 2016. The consolidated state court actions remain pending. The pending consolidated state court actions allege, among other things, that members of HEI's Board of Directors (Board) breached their fiduciary duties in connection with the proposed transaction, and that the Merger Agreement involved an unfair price, was the product of an inadequate sales process, and contained unreasonable deal protection devices that purportedly precluded competing offers. The complaints further allege that HEI, NEE and/or its acquisition subsidiaries aided and abetted the purported breaches of fiduciary duty. The plaintiffs in the pending consolidated state actions also allege that JP Morgan had a conflict of interest in advising HEI because JP Morgan and its affiliates had business ties to and investments in NEE. The consolidated state action also alleges that the HEI Board violated its fiduciary duties by omitting material facts from the Registration Statement on Form S-4. The plaintiffs in these lawsuits seek, among other things, (i) a declaration that the Merger Agreement was entered into in breach of HEI's directors' fiduciary duties, (ii) an injunction enjoining the HEI Board from consummating the Merger, (iii) an order directing the HEI Board to exercise their duties to obtain a transaction which is in the best interests of HEI's stockholders, (iv) a rescission of the Merger to the extent that it is consummated, and/or (v) damages suffered as a result of the defendants' alleged actions. HEI and Hawaiian Electric believe the allegations in the complaints are without merit and are moot as a result of the termination of the Merger Agreement.

Termination of proposed merger and other matters

On December 3, 2014, HEI, NextEra Energy, Inc., a Florida corporation (NEE), NEE Acquisition Sub I, LLC, a Delaware limited liability company and a wholly owned subsidiary of NEE (Merger Sub II) and NEE Acquisition Sub II, Inc., a Delaware corporation and a wholly owned subsidiary of NEE (Merger Sub I), entered into an Agreement and Plan of Merger (the Merger Agreement). The Merger Agreement provided for Merger Sub I to merge with and into HEI (the Initial Merger), with HEI surviving, and then for HEI to merge with and into Merger Sub II, with Merger Sub II surviving as a wholly owned subsidiary of NEE (the Merger). The Merger Agreement contemplated that, immediately prior to the closing of the Merger, HEI would distribute to its shareholders all of the issued and outstanding shares of common stock of ASB Hawaii, Inc. (ASB Hawaii), the direct parent company of ASB (such distribution referred to as the Spin-Off), with ASB Hawaii becoming a new public company.

The closing of the Merger was subject to various conditions, including, among others, receipt of regulatory approval from the Hawaii Public Utilities Commission (PUC). In January 2015, NEE and Hawaiian Electric filed an application with the PUC requesting approval of the proposed Merger (under which Hawaiian Electric would become a wholly-owned indirect subsidiary of NEE). On July 15, 2016, the PUC dismissed the application without prejudice.

On July 16, 2016, pursuant to the terms of the Merger Agreement, NEE provided written notice to HEI indicating that NEE was terminating the Merger Agreement effective immediately. Pursuant to the terms of the Merger Agreement, on July 19, 2016, NEE paid HEI a $90 million termination fee and $5 million for the reimbursement of expenses associated with the transaction. In the third quarter of 2016, HEI will recognize for financial reporting purposes the termination fee and reimbursement of expenses (net of taxes), additional tax benefits of approximately $7.8 million on the previously non-tax-deductible merger- and spin-off-related expenses incurred through June 30, 2016, and merger- and spin-off-related expenses incurred in the third quarter of 2016 (net of tax benefits). The Spin-Off of ASB Hawaii was cancelled as it was cross-conditioned on the merger consummation.

On May 18, 2016, the Utilities filed an application for an LNG supply and transport agreement and LNG-related capital equipment to utilize natural gas at certain designated facilities, and two applications to commit funds for and waive from the PUC’s Framework for Competitive Bidding the Kahe Combined Cycle Generating Unit project. The three filings were conditioned on PUC approval of the Utilities’ and NextEra Energy’s joint application for approval of a merger between the two parties. On July 19, 2016, the Utilities filed withdrawals of these three applications, noting that because the merger application approval condition was not satisfied, the underlying projects would not go forward. On July 21, 2016, the PUC issued orders closing all three dockets.

Litigation. HEI and its subsidiaries are subject to various legal proceedings that arise from time to time. Some of these proceedings may seek relief or damages in amounts that may be substantial. Because these proceedings are complex, many years may pass before they are resolved, and it is not feasible to predict their outcomes. Some of these proceedings involve claims HEI and Hawaiian Electric believe may be covered by insurance, and HEI and Hawaiian Electric have advised their insurance carriers accordingly.

Since the December 3, 2014 announcement of the merger agreement, eight purported class action complaints were filed in the Circuit Court of the First Circuit for the State of Hawaii by alleged stockholders of HEI against HEI, Hawaiian Electric (in one complaint), the individual directors of HEI, NEE and NEE's acquisition subsidiaries. The lawsuits are captioned as follows: Miller v. Hawaiian Electric Industries, Inc., et al., Case No. 14-1-2531-12 KTN (December 15, 2014) (the Miller Action); Walsh v. Hawaiian Electric Industries, Inc., et al., Case No. 14-1-2541-12 JHC (December 15, 2014) (the Walsh Action); Stein v. Hawaiian Electric Industries, Inc., et al., Case No. 14-1-2555-12 KTN (December 17, 2014) (the Stein Action); Brown v. Hawaiian Electric Industries, Inc., et al., Case No. 14-1-2643-12 RAN (December 30, 2014) (the Brown Action); Cohn v. Hawaiian Electric Industries, Inc., et al., Case No. 14-1-2642-12 KTN (December 30, 2014) (the Cohn State Action); Guenther v. Watanabe, et al., Case No. 15-1-003-01 ECN (January 2, 2015) (the Guenther Action); Hudson v. Hawaiian Electric Industries, Inc., et al., Case No. 15-1-0013-01 JHC (January 5, 2015) (the Hudson Action); Grieco v. Hawaiian Electric Industries, Inc., et al., Case No. 15-1-0094-01 KKS (January 21, 2015) (the Grieco Action). On January 12, 2015, plaintiffs in the Miller Action, the Walsh Action, the Stein Action, the Brown Action, the Guenther Action, and the Hudson Action filed a motion to consolidate their actions and to appoint co-lead counsel. On January 23, 2015, the Cohn State Action was voluntarily dismissed. On January 27, 2015, Cohn filed a purported class action captioned Cohn v. Hawaiian Electric Industries, Inc., et al., Civil No. 15-00029-JMS-RLP in the United States District Court for the District of Hawaii against HEI, the individual directors of HEI, NEE and NEE’s acquisition subsidiaries (the Cohn Federal Action). On February 13, 2015, the state court orally granted the plaintiffs’ motions to consolidate the seven state court actions and appoint co-lead counsel and entered a written order granting the motions on March 6, 2015. On March 10, 2015, plaintiffs filed a first consolidated complaint in state court that added as a defendant J.P. Morgan Securities, LLC (JP Morgan), the financial advisor to HEI for the Merger, and deleted Hawaiian Electric Company, Inc. as a defendant and concurrently served a first request for production of documents on HEI and the individual directors. On March 17, 2015, plaintiffs filed a motion for limited expedited discovery in the consolidated state action and thereafter on March 25, 2015 withdrew their request for limited discovery and first request for production of documents as a result of the parties’ agreement to conduct certain specified limited discovery which included a stipulated confidentiality agreement and protective order protecting the confidentiality of certain information exchanged between the parties in connection with discovery in the consolidated action that was filed on April 6, 2015. On April 15 and 17, 2015, a deposition of a representative of HEI and a representative of JP Morgan were taken, respectively. On April 21, 2015, plaintiffs confirmed the cancellation of the preliminary injunction hearing that had been scheduled for May 5, 2015 in the consolidated action and on April 23, 2015, the state court entered a stipulation and order to extend indefinitely the time to answer or otherwise respond to the first amended consolidated complaint. On April 30, 2015, the state court entered a consolidated case management order confirming the consolidated treatment of the state actions for purposes of case management, pretrial discovery, procedural and other matters. On May 27, 2015, the federal court entered a stipulation and order approving the stipulation of the parties to stay the Cohn Federal Action pending the resolution of the state court consolidated action and administratively closing the Cohn Federal Action without prejudice to any party. On May 29, 2015, the state court entered a stipulated order amending the consolidated caption to read IN RE Consolidated HEI Shareholder Cases, Master File No. Civil No. 1CC15-1-HEI, to add JP Morgan as a named defendant in each individual action, add the caption for the Grieco Action, and remove Hawaiian Electric Company, Inc. from the caption in the Brown Action. In October 2015, several depositions of HEI representatives were taken in the state consolidated action. On February 9, 2016, plaintiffs filed an ex parte motion for second extension of time to file the pretrial statement in the state consolidated action from February 15, 2016 to August 15, 2016.

Following the termination of the Merger Agreement, a stipulation and order for dismissal with prejudice of all claims and parties was entered by the court in the Cohn Federal Action on July 22, 2016. The consolidated state court actions remain pending.

The pending consolidated state court actions allege, among other things, that members of HEI's Board of Directors (Board) breached their fiduciary duties in connection with the proposed transaction, and that the Merger Agreement involved an unfair price, was the product of an inadequate sales process, and contained unreasonable deal protection devices that purportedly precluded competing offers. The complaints further allege that HEI, NEE and/or its acquisition subsidiaries aided and abetted the purported breaches of fiduciary duty. The plaintiffs in the pending consolidated state actions also allege that JP Morgan had a conflict of interest in advising HEI because JP Morgan and its affiliates had business ties to and investments in NEE. The consolidated state action also alleges that the HEI Board violated its fiduciary duties by omitting material facts from the Registration Statement on Form S-4.

The plaintiffs in these lawsuits seek, among other things, (i) a declaration that the Merger Agreement was entered into in breach of HEI's directors' fiduciary duties, (ii) an injunction enjoining the HEI Board from consummating the Merger, (iii) an order directing the HEI Board to exercise their duties to obtain a transaction which is in the best interests of HEI's stockholders, (iv) a rescission of the Merger to the extent that it is consummated, and/or (v) damages suffered as a result of the defendants' alleged actions.

HEI and Hawaiian Electric believe the allegations in the complaints are without merit and are moot as a result of the termination of the Merger Agreement.