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Electric utility segment - Unconsolidated variable interest entities (Details) $ in Thousands | 3 Months Ended |
--- | --- | ---
Mar. 31, 2018 USD ($) agreement entity | Dec. 31, 2017 USD ($)
Hawaiian Electric Company |  |
Power purchase agreement |  |
Number of power purchase agreements (PPAs) (in agreements) | agreement | 5 |
Number of entities currently required to be consolidated as VIEs (in entities) | entity | 0 |
Number of IPPs | entity | 3 |
Number of firm capacity producers declining to provide financial information to determine primary beneficiary status (in entities) | entity | 2 |
Minimum potential number of IPP entities consolidated into company in the future (in entities) | entity | 1 |
Variable Interest Entity, Not Primary Beneficiary |  |
Unconsolidated variable interest entities |  |
Investment in 2004 Debentures | $ 51,500 | $ 51,500
Interest income | $ 800 |
Variable Interest Entity, Not Primary Beneficiary | Hawaiian Electric Company |  |
Unconsolidated variable interest entities |  |
Percent of ownership in Trust III (as a percent) | 100.00% |
Variable Interest Entity, Not Primary Beneficiary | Hawaiian Electric Company | 2004 Trust Preferred Securities |  |
Unconsolidated variable interest entities |  |
Balance of Trust Securities | $ 50,000 | 50,000
Dividend distributions on Trust Preferred Securities | 800 |
Variable Interest Entity, Not Primary Beneficiary | Hawaiian Electric Company | Trust Common Securities |  |
Unconsolidated variable interest entities |  |
Balance of Trust Securities | 1,500 | $ 1,500
Common dividend | $ 25 |

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- Definition Preferred securities that embody an unconditional obligation requiring the issuer to redeem the securities by transferring the assets at a specified or determinable date (or dates) or upon an event that is certain to occur, that are issued by a trust to outside investors where the trust uses the proceeds of the issuance of those securities to purchase an equivalent amount of junior subordinated debentures or other loans having stated maturities. + References No definition available. + Details
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- Definition Adjustment to net income reflecting the dividends paid to the holders of Trust Common Securities. + References No definition available. + Details
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- Definition The minimum number of potential IPP's that could be required to be consolidation into the Company in the future based on new financial information provided by IIP's used to determine VIE relationship. + References No definition available. + Details
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- Definition Number Of Independent Power Producers + References No definition available. + Details
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- Definition Represents the number of firm power purchase agreements entered into, by the company. + References No definition available. + Details
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- Definition -- None. No documentation exists for this element. -- + References No definition available. + Details
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- Definition Represents the number of entities not required to be consolidated as VIEs. + References No definition available. + Details
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- Definition The amount of interest incurred to a trust which has issued trust-preferred securities. In order to issue trust preferred securities, a sponsor forms a trust by investing a nominal amount of cash to purchase all of the voting common stock of the trust. The trust issues nonvoting, mandatorily redeemable preferred securities to outside investors in exchange for cash. The proceeds received from the issuance of the preferred securities, together with the cash received for issuing the common stock to the sponsor, is then loaned to the sponsor in exchange for a note which has the same terms as the trust preferred securities. Trust preferred securities possesses characteristics of both equity and debt issues and are generally issued by bank holding companies. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 480 -SubTopic 10 -Section 55 -Paragraph 6 -URI http://asc.fasb.org/extlink&oid=6924035&loc=d3e22274-110880 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 225 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-04(9)) -URI http://asc.fasb.org/extlink&oid=6879574&loc=d3e536633-122882 + Details
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- Definition Amount before accretion (amortization) of purchase discount (premium) of interest income on nonoperating securities. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 225 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03.7(b)) -URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688 + 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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- Definition Percentage of the Variable Interest Entity's (VIE) voting interest owned by (or beneficial interest in) the reporting entity (directly or indirectly). + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 810 -SubTopic 10 -Section 50 -Paragraph 5A -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=64801991&loc=SL6759159-111685 + Details
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