v3.25.4

Capitalization (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended	14 Months Ended
	Dec. 31, 2025	Dec. 31, 2025	Dec. 31, 2024	Oct. 29, 2024
Subsidiary, Sale of Stock [Line Items]
Common stock, shares authorized (in shares)	70,000,000	70,000,000	70,000,000
Common stock, par value (in usd per share)	$ 0.001	$ 0.001	$ 0.001
Common stock, shares issued (in shares)	36,118,242	36,118,242	33,629,169
Common stock, shares outstanding (in shares)	36,118,242	36,118,242	33,629,169
Preferred stock, shares authorized (in shares)	1,000,000	1,000,000	1,000,000
Preferred stock, par value (in usd per share)	$ 0.001	$ 0.001	$ 0.001
Preferred stock, shares issued (in shares)	0	0	0
Preferred stock, shares outstanding (in shares)	0	0	0
At The Market Offering
Subsidiary, Sale of Stock [Line Items]
Common stock, par value (in usd per share)				$ 0.001
Aggregate gross sales price (up to)				$ 200,000
Shares issued in offering (in shares)	2,387,846	2,763,359
Weighted average price per share (in usd per share)	$ 51.90	$ 52.39
Net proceeds from stock offering	$ 122,806	$ 142,975
Total equity distribution	$ 55,239	$ 55,239

Sale of Stock, Aggregate Gross Sales Price

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Sale of Stock, Total Equity Distribution Agreement Remaining

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Sale of Stock, Weighted Average Price Per Share

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Face amount or stated value per share of common stock.

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The maximum number of common shares permitted to be issued by an entity's charter and bylaws.

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Total number of common shares of an entity that have been sold or granted to shareholders (includes common shares that were issued, repurchased and remain in the treasury). These shares represent capital invested by the firm's shareholders and owners, and may be all or only a portion of the number of shares authorized. Shares issued include shares outstanding and shares held in the treasury.

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Number of shares of common stock outstanding. Common stock represent the ownership interest in a corporation.

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Face amount or stated value per share of preferred stock nonredeemable or redeemable solely at the option of the issuer.

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The maximum number of nonredeemable preferred shares (or preferred stock redeemable solely at the option of the issuer) permitted to be issued by an entity's charter and bylaws.

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Number of shares issued for nonredeemable preferred shares and preferred shares redeemable solely at option of issuer. Includes, but is not limited to, preferred shares issued, repurchased, and held as treasury shares. Excludes preferred shares classified as debt.

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Aggregate share number for all nonredeemable preferred stock (or preferred stock redeemable solely at the option of the issuer) held by stockholders. Does not include preferred shares that have been repurchased.

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Cash received on stock transaction after deduction of issuance costs.

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The number of shares issued or sold by the subsidiary or equity method investee per stock transaction.

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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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H2O AMERICA 10-K