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- Definition

Number Of Wholly-Owned Subsidiaries

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- Definition

Public Utilities, Power Produced By Power Plant

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Amount of write-down of assets recognized in the income statement. Includes, but is not limited to, losses from tangible assets, intangible assets and goodwill.

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Amount of consideration received or receivable for the disposal of assets and liabilities, including discontinued operation.

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- Definition

The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

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This item represents the carrying amount on the entity's balance sheet of its investment in common stock of an equity method investee. This is not an indicator of the fair value of the investment, rather it is the initial cost adjusted for the entity's share of earnings and losses of the investee, adjusted for any distributions (dividends) and other than temporary impairment (OTTI) losses recognized.

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Amount of gain (loss) from sale and disposal of integrated set of activities and assets capable of being conducted and managed for purpose of providing return in form of dividend, lower cost, or other economic benefit to investor, owner, member and participant.

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The amount deducted from an entities' taxes, reflecting a percentage of an amount invested in certain assets spread over the useful life of those assets; includes deferred investment tax credits.

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Amount of equity (deficit) attributable to noncontrolling interest. Excludes temporary equity.

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The equity interest of noncontrolling shareholders, partners or other equity holders in consolidated entity.

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- Definition

Number of operating segments. An operating segment is a component of an enterprise: (a) that engages in business activities from which it may earn revenues and incur expenses (including revenues and expenses relating to transactions with other components of the same enterprise), (b) whose operating results are regularly reviewed by the enterprise's chief operating decision maker to make decisions about resources to be allocated to the segment and assess its performance, and (c) for which discrete financial information is available. An operating segment may engage in business activities for which it has yet to earn revenues, for example, start-up operations may be operating segments before earning revenues.

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Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements.

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The amount of cash paid for the settlement of litigation or for other legal issues during the period.

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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.

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No definition available.

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Segment financial information - Narrative (Details) $ in Millions			3 Months Ended	9 Months Ended	12 Months Ended
	Dec. 31, 2024 segment	Dec. 30, 2024 USD ($)	Mar. 31, 2025 USD ($)	Sep. 30, 2025 USD ($) subsidiary	Dec. 30, 2024 USD ($) segment	Dec. 31, 2017 MW
Segment financial information
Number of reportable segments \| segment	1				2
Number of operating segments \| segment	1				2
GLST1, LLC
Segment financial information
Membership interest			60.00%
Investment in unconsolidated affiliate				$ 287.3
Hamakua Energy
Segment financial information
Power produced by power plants (in megawatts) \| MW						60
Hamakua Holdings, LLC
Segment financial information
Number of wholly-owned subsidiaries \| subsidiary				2
GLST1, LLC
Segment financial information
First settlement payment				$ 479.0
American Savings Bank (ASB) \| ASB Hawaii, Inc
Segment financial information
Minority ownership percentage				9.90%
Noncontrolling ownership interest				$ 44.6
Discontinued Operations, Disposed of by Sale \| American Savings Bank (ASB)
Segment financial information
Ownership percentage disposed	90.10%	90.10%
Consideration amount		$ 405.5			$ 405.5
Disposal Group, Held-for-Sale, Not Discontinued Operations \| Pacific Current
Segment financial information
Asset impairment charges				0.2
Investment tax credit				$ 5.3
Disposal Group, Disposed of by Sale, Not Discontinued Operations \| Hamakua Holdings, LLC
Segment financial information
Loss on sale			$ 13.2