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Electric utility segment - Taxes (Details) - USD ($) $ in Millions | 3 Months Ended | 12 Months Ended
--- | --- | ---
Mar. 31, 2016 | Mar. 31, 2015 | Dec. 31, 2015
Revenue taxes |  |  |
Expected increase in income tax depreciation expense |  |  | $ 117
Hawaiian Electric Company, Inc. and Subsidiaries |  |  |
Revenue taxes |  |  |
Revenue taxes included in operating revenues and in taxes other than income taxes expense | $ 43 | $ 51 |

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- Definition Represents the utility revenue taxes included in operating revenues and in taxes, other than income taxes expense. + References No definition available. + Details
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- Definition Income Tax Expense, Expected Increase In Depreciation Expense, Amount + References No definition available. + Details
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
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- Details
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