Background and Organization	6 Months Ended
Jun. 30, 2026
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Background and Organization	Note 1 – Background and Organization Nature of Operations. The Company, a Delaware corporation, is a holding company owning all of the shares of common stock of Southwest Gas, a California corporation. The Company’s common stock trades under the ticker symbol “SWX.” Until the deconsolidation of Centuri in August 2025, the Company’s businesses were managed within two separate reportable segments, our Natural Gas Distribution segment (Southwest Gas) and our Utility Infrastructure Services segment (Centuri). After August 2025, our business is solely comprised of our Natural Gas Distribution segment. Southwest Gas is engaged in the business of purchasing, distributing, and transporting natural gas for customers in portions of Arizona, Nevada, and California. Public utility rates, practices, facilities, and service territories of Southwest Gas are subject to regulatory oversight. The timing and amount of rate relief can materially impact results of operations. Natural gas purchases and the timing of related recoveries can materially impact liquidity. While mechanisms exist in all states in which Southwest Gas operates, which decouple authorized operating cost recovery and profitability from the volume of natural gas sold, thereby also incentivizing energy conservation, results for the Natural Gas Distribution segment are higher during winter periods due to the seasonality incorporated in its regulatory rate structures.

Background and Organization

6 Months Ended

Jun. 30, 2026

Organization, Consolidation and Presentation of Financial Statements [Abstract]

Note 1 – Background and Organization

Nature of Operations. The Company, a Delaware corporation, is a holding company owning all of the shares of common stock of Southwest Gas, a California corporation. The Company’s common stock trades under the ticker symbol “SWX.”

Until the deconsolidation of Centuri in August 2025, the Company’s businesses were managed within two separate reportable segments, our Natural Gas Distribution segment (Southwest Gas) and our Utility Infrastructure Services segment (Centuri). After August 2025, our business is solely comprised of our Natural Gas Distribution segment.

Southwest Gas is engaged in the business of purchasing, distributing, and transporting natural gas for customers in portions of Arizona, Nevada, and California. Public utility rates, practices, facilities, and service territories of Southwest Gas are subject to regulatory oversight. The timing and amount of rate relief can materially impact results of operations. Natural gas purchases and the timing of related recoveries can materially impact liquidity. While mechanisms exist in all states in which Southwest Gas operates, which decouple authorized operating cost recovery and profitability from the volume of natural gas sold, thereby also incentivizing energy conservation, results for the Natural Gas Distribution segment are higher during winter periods due to the seasonality incorporated in its regulatory rate structures.