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Proposed Merger (Details) |  |  | 1 Months Ended | 4 Months Ended |
--- | --- | --- | --- | --- | ---
Aug. 07, 2015 | Dec. 03, 2014 USD ($) $ / shares shares | Jul. 31, 2015 intervener | Jan. 31, 2015 USD ($) | Mar. 31, 2015 complaint | Apr. 30, 2015 action
Business Acquisition [Line Items] |  |  |  |  |  |
Number of purported class action complaints filed | complaint |  |  |  |  | 8 |
NextEra Energy, Inc Merger |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |
Merger share conversion ratio | shares |  | 0.2413 |  |  |  |
Minimum percentage of shares from which holders approval needed for merger |  | 75.00% |  |  |  |
Merger agreement contract extension |  | 6 months |  |  |  |
Merger contract termination fee | $ |  | $ 90,000,000 |  |  |  |
Maximum expenses paid to party for cancellation of merger | $ |  | $ 5,000,000 |  |  |  |
Minimum period that entity agrees not to submit applications for general base rate increase |  |  |  | 4 years |  |
Approximate amount of cumulative savings for customers due to forgone recoveries | $ |  |  |  | $ 60,000,000 |  |
NextEra Energy, Inc Merger | Subsequent Event |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |
Regulatory waiting period | 30 days |  |  |  |  |
Number of interveners |  |  | 28 |  |  |
Number of interveners who opposed |  |  | 11 |  |  |
Number of interveners opposed who approved conditionally |  |  | 11 |  |  |
Number of interveners who made no recommendation |  |  | 6 |  |  |
Hawaiian Electric Company, Inc. and Subsidiaries | NextEra Energy, Inc Merger |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |
Special dividend | $ / shares |  | $ 0.50 |  |  |  |
In re Consolidated HEI Shareholder Cases |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |
Consolidated number of state actions | action |  |  |  |  |  | 7

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