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Represents the consolidated subsidiary debt to total consolidated capitalization ratio which the entity is required to maintain pursuant to a debt covenant.

No definition available.

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Period Type:	instant

Represents the nonconsolidated capitalization ratio, which the entity is required to maintain pursuant to a debt covenant.

No definition available.

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Debt Instrument, Covenant, Threshold Debt Proceeds Applied As Repayment Of Term Loan

No definition available.

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Debt Instrument, Number Of Instruments Entered Into During Period

No definition available.

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Line Of Credit Facility, Additional Borrowing Capacity

No definition available.

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

Represents the number of financial institutions with which the entity entered into a revolving Non Collateralized credit agreement with a letter of credit sub-facility.

No definition available.

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Percentage points added to the reference rate to compute the variable rate on the debt instrument.

No definition available.

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Data Type:	num:percentItemType
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Contractual interest rate for funds borrowed, under the debt agreement.

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Period Type:	instant

Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

No definition available.

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Gross amount of debt extinguished.

No definition available.

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The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

No definition available.

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The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

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Period Type:	instant

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

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The fee, expressed as a percentage of the line of credit facility, for available but unused credit capacity under the credit facility.

No definition available.

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Amount of borrowings classified as other, maturing within one year or the normal operating cycle, if longer.

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The cash inflow from a debt initially having maturity due after one year or beyond the operating cycle, if longer.

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Amount of cash inflow from contractual arrangement with the lender, including but not limited to, letter of credit, standby letter of credit and revolving credit arrangements.

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The cash outflow for a borrowing having initial term of repayment within one year or the normal operating cycle, if longer.

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Reflects the total carrying amount as of the balance sheet date of debt having initial terms less than one year or the normal operating cycle, if longer.

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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.

No definition available.

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Weighted average interest rate of short-term debt outstanding calculated at point in time.

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Name:	us-gaap_ShortTermDebtTypeAxis=he_TermLoanMember
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