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v3.25.3

Fair value measurements - Carrying or Notional Amount, Fair Value and Placement in the Fair Value Hierarchy of the Company’s Financial Instruments (Details) - USD ($) $ in Thousands | Sep. 30, 2025 | Aug. 01, 2025 | Dec. 31, 2024
--- | --- | --- | ---
Significant other observable inputs (Level 2) |  |  |
Financial assets |  |  |
Derivative assets |  | $ 1,000 |
Carrying or notional amount |  |  |
Financial assets |  |  |
Derivative assets |  |  | $ 29,312
Financial liabilities |  |  |
Short-term borrowings, net |  |  | 48,623
Long-term debt, net | $ 2,438,691 |  | 2,799,558
Carrying or notional amount | Money Market Funds |  |  |
Financial assets |  |  |
Money market mutual funds | 925,258 |  | 1,162,259
Carrying or notional amount | Hawaiian Electric Company, Inc. and Subsidiaries |  |  |
Financial liabilities |  |  |
Short-term borrowings, net |  |  | 48,623
Long-term debt, net | 2,182,533 |  | 1,901,214
Carrying or notional amount | Hawaiian Electric Company, Inc. and Subsidiaries | Money Market Funds |  |  |
Financial assets |  |  |
Money market mutual funds | 402,575 |  | 115,599
Estimated fair value |  |  |
Financial assets |  |  |
Derivative assets |  |  | $ 1,629
Derivative asset, statement of financial position |  |  | Other
Financial liabilities |  |  |
Short-term borrowings, net |  |  | $ 48,623
Long-term debt, net | 2,104,038 |  | 2,196,403
Estimated fair value | Money Market Funds |  |  |
Financial assets |  |  |
Money market mutual funds | 925,258 |  | 1,162,259
Estimated fair value | Hawaiian Electric Company, Inc. and Subsidiaries |  |  |
Financial liabilities |  |  |
Short-term borrowings, net |  |  | 48,623
Long-term debt, net | 1,871,292 |  | 1,446,316
Estimated fair value | Hawaiian Electric Company, Inc. and Subsidiaries | Money Market Funds |  |  |
Financial assets |  |  |
Money market mutual funds | 402,575 |  | 115,599
Estimated fair value | Quoted prices in active markets for identical assets (Level 1) |  |  |
Financial assets |  |  |
Derivative assets |  |  | 0
Financial liabilities |  |  |
Short-term borrowings, net |  |  | 0
Long-term debt, net | 0 |  | 0
Estimated fair value | Quoted prices in active markets for identical assets (Level 1) | Money Market Funds |  |  |
Financial assets |  |  |
Money market mutual funds | 925,258 |  | 1,162,259
Estimated fair value | Quoted prices in active markets for identical assets (Level 1) | Hawaiian Electric Company, Inc. and Subsidiaries |  |  |
Financial liabilities |  |  |
Short-term borrowings, net |  |  | 0
Long-term debt, net | 0 |  | 0
Estimated fair value | Quoted prices in active markets for identical assets (Level 1) | Hawaiian Electric Company, Inc. and Subsidiaries | Money Market Funds |  |  |
Financial assets |  |  |
Money market mutual funds | 402,575 |  | 115,599
Estimated fair value | Significant other observable inputs (Level 2) |  |  |
Financial assets |  |  |
Derivative assets |  |  | 1,629
Financial liabilities |  |  |
Short-term borrowings, net |  |  | 48,623
Long-term debt, net | 2,104,038 |  | 2,196,403
Estimated fair value | Significant other observable inputs (Level 2) | Money Market Funds |  |  |
Financial assets |  |  |
Money market mutual funds | 0 |  | 0
Estimated fair value | Significant other observable inputs (Level 2) | Hawaiian Electric Company, Inc. and Subsidiaries |  |  |
Financial liabilities |  |  |
Short-term borrowings, net |  |  | 48,623
Long-term debt, net | 1,871,292 |  | 1,446,316
Estimated fair value | Significant other observable inputs (Level 2) | Hawaiian Electric Company, Inc. and Subsidiaries | Money Market Funds |  |  |
Financial assets |  |  |
Money market mutual funds | $ 0 |  | $ 0

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- Definition Fair value, after the effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. 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- Definition The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 820 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (bbb)(2)(i) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482106/820-10-50-2 Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 820 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (bbb)(2) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482106/820-10-50-2 Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 820 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (bbb)(1) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482106/820-10-50-2 Reference 4: http://www.xbrl.org/2003/role/exampleRef -Name Accounting Standards Codification -Section 55 -Paragraph 10 -SubTopic 10 -Topic 825 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482881/825-10-55-10 Reference 5: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 825 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 28 -Subparagraph (c)(1) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482907/825-10-50-28 Reference 6: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 825 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 11 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482907/825-10-50-11 Reference 7: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 825 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 11 -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482907/825-10-50-11 Reference 8: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 825 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 10 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482907/825-10-50-10 Reference 9: http://www.xbrl.org/2003/role/exampleRef -Topic 825 -SubTopic 10 -Name Accounting Standards Codification -Section 55 -Paragraph 12 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482881/825-10-55-12 Reference 10: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 820 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482106/820-10-50-2 + Details
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