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Electric utility segment - Most recent rate proceedings (Details) - USD ($) $ in Thousands | 1 Months Ended |
--- | --- | ---
Dec. 31, 2021 | Mar. 31, 2022
Regulatory Projects and Legal Obligations [Line Items] |  |
Regulatory assets | $ 565,543 | $ 559,161
Hawaiian Electric Company, Inc. and Subsidiaries |  |
Regulatory Projects and Legal Obligations [Line Items] |  |
Regulatory assets |  | $ 27,800
Hawaiian Electric Company, Inc. and Subsidiaries | COVID-19 |  |
Regulatory Projects and Legal Obligations [Line Items] |  |
Customer bill forgiveness | $ 2,000 |

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- Definition The amount for the individual regulatory asset as itemized in a table of regulatory assets as of the end of the period. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 980 -SubTopic 340 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6499975&loc=d3e44250-110382 + Details
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- Details
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