Summary of Significant Accounting Policies - Schedule of Other Property and Investments (Details) - USD ($) $ in Thousands |
Jun. 30, 2026 |
Dec. 31, 2025 |
|---|---|---|
| Property, Plant, and Equipment [Line Items] | ||
| Other property and investments | $ 10,216 | $ 8,879 |
| Total | 181,406 | 178,826 |
| Southwest Gas Corporation | ||
| Property, Plant, and Equipment [Line Items] | ||
| Net cash surrender value of COLI policies | 168,916 | 165,551 |
| Other property and investments | 2,274 | 4,396 |
| Total | $ 171,190 | $ 169,947 |
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- Definition Aggregate carrying amount, as of the balance sheet date, of other property and investments not separately presented elsewhere in the balance sheet. No definition available.
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- Definition Carrying amount as of the balance sheet date of amounts which could be received based on the terms of the insurance contract upon surrendering life policies owned by the entity. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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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. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Amount, after accumulated depreciation, depletion, and amortization, of property, plant, and equipment; classified as other. Includes, but is not limited to, land and land improvement; building; machinery and equipment; furniture and fixture; and work of art, historical treasure, or similar asset classified as collection. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Details
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