Background, Organization, and Summary of Significant Accounting Policies (Policies)	3 Months Ended
Mar. 31, 2022
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Nature of Operations	Nature of Operations. Southwest Gas Holdings, Inc. (together with its subsidiaries, the “Company”) is a holding company, owning all of the shares of common stock of Southwest Gas Corporation (“Southwest” or the “natural gas distribution” segment), all of the shares of common stock of Centuri Group, Inc. (“Centuri,” or the “utility infrastructure services” segment), and all of the shares of common stock of MountainWest Pipelines Holding Company (“MountainWest,” or the “pipeline and storage” segment). The Company completed the acquisition of Dominion Energy Questar Pipeline, LLC and related entities (“Questar Pipelines”) in December 2021. Following the completion of the acquisition, the Company formed MountainWest which owns all of the membership interests in Questar Pipelines. In April 2022, the Company completed a general rebranding of the Questar Pipelines entities under the MountainWest name. The acquired operations further diversify the Company’s business in the midstream sector, with an expansion of interstate natural gas pipelines and underground storage services, primarily composed of regulated operations under the jurisdiction of the Federal Energy Regulatory Commission (the “FERC”), thereby expanding natural gas transportation services into Utah, Wyoming, and Colorado. See Note 8 - Business Acquisitions for more information. Southwest 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 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. Results for the natural gas distribution segment are higher during winter periods due to the seasonality incorporated in its regulatory rate structures. Centuri is a strategic utility infrastructure services company dedicated to partnering with North America’s gas and electric providers to build and maintain the energy network that powers millions of homes across the United States (“U.S.”) and Canada. Centuri derives revenue primarily from installation, replacement, repair, and maintenance of energy networks. Centuri operates in the U.S., primarily as NPL, Neuco, Linetec, and Riggs Distler, and in Canada, primarily as NPL Canada. Utility infrastructure services activity is seasonal in many of Centuri’s operating areas. Peak periods are the summer and fall months in colder climate areas, such as the northeastern and midwestern U.S. and in Canada. In warmer climate areas, such as the southwestern and southeastern U.S., utility infrastructure services activity continues year round.
Basis of Presentation	Basis of Presentation. The condensed consolidated financial statements of Southwest Gas Holdings, Inc. and subsidiaries and Southwest included herein have been prepared pursuant to the rules and regulations of the Securities and Exchange Commission (the “SEC”). The year-end condensed balance sheet data was derived from audited financial statements. Certain information and footnote disclosures normally included in financial statements prepared in accordance with U.S. generally accepted accounting principles (“U.S. GAAP”) have been condensed or omitted pursuant to such rules and regulations. No substantive change has occurred with regard to the Company’s business segments on the whole. The preparation of the condensed consolidated financial statements requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities as of the date of the financial statements, and the reported amounts of revenues and expenses during the reporting period. Actual results could differ from those estimates. In the opinion of management, all adjustments, consisting of normal recurring items and estimates necessary for a fair depiction of results for the interim periods, have been made. These condensed consolidated financial statements should be read in conjunction with the consolidated financial statements and notes thereto included in the 2021 Annual Report to Stockholders, which is incorporated by reference into the 2021 Form 10-K.
Fair Value Measurements
Cash and Cash Equivalents	Cash and Cash Equivalents. Cash and cash equivalents include money market fund investments totaling approximately $169 million and $231 million, for Southwest and the Company, respectively, at March 31, 2022, and $20 million for the Company as of December 31, 2021. The balance for Southwest as of December 31, 2021 was insignificant. These investments fall within Level 2 of the fair value hierarchy, due to the asset valuation methods used by money market funds. The Company had $7 million in restricted cash included in Cash and cash equivalents at March 31, 2022, related to residual proceeds received from its March 2022 common stock offering to be applied against its 364-day Term Loan Facility, which occurred in April 2022. The restricted cash balance is included in Cash and cash equivalents within the Company’s Condensed Consolidated Statement of Cash Flows as of March 31, 2022.Non-cash investing activities for the Company and Southwest include capital expenditures that were not yet paid totaling approximately $26.1 million at March 31, 2022, and $19.4 million at December 31, 2021.
Accounts Receivable, net of allowances	Accounts Receivable, net of allowances. Southwest lifted the moratorium on disconnection of natural gas service for non-payment in Arizona and Nevada in September 2021, which was initiated (at the same time as a moratorium on late fees) in March 2020 in response to the COVID-19 pandemic. The moratorium on disconnection in California ended in November 2021. Southwest recommenced assessing late fees on past-due balances in Arizona and Nevada in April 2021, and in California in August 2021. Southwest continues to actively work with customers experiencing financial hardship by means of flexible payment options, partnering with assistance agencies and participating in state-funded arrearage payment assistance programs. Deferred Purchased Gas Costs. The various regulatory commissions have established procedures to enable the rate-regulated companies to adjust billing rates for changes in the cost of natural gas purchased. The difference between the current cost of gas purchased and the cost of gas recovered in billed rates is deferred. Generally, these deferred amounts are recovered or refunded within one year. In mid-February 2021, the central U.S. experienced extreme cold temperatures, which increased natural gas demand and caused supply issues due to wellhead freeze-offs, power outages, or other adverse operating conditions upstream of Southwest’s distribution systems. These conditions caused daily natural gas prices to reach unprecedented levels. During this time, Southwest secured natural gas supplies, albeit at substantially higher prices, maintaining service to its customers. The incremental cost for these supplies was approximately $250 million, funded using a 364-day $250 million term loan executed in March 2021. The incremental gas costs were included, for collection from customers, as part of the purchased gas adjustment (“PGA”) mechanisms. The term loan was amended in March 2022 to extend the maturity date to March 2023 due to gas prices that, while not at levels incurred during the 2021 freeze, continue to be elevated (see Note 5 – Debt).
Deferred Purchased Gas Costs	Deferred Purchased Gas Costs. The various regulatory commissions have established procedures to enable the rate-regulated companies to adjust billing rates for changes in the cost of natural gas purchased. The difference between the current cost of gas purchased and the cost of gas recovered in billed rates is deferred. Generally, these deferred amounts are recovered or refunded within one year. In mid-February 2021, the central U.S. experienced extreme cold temperatures, which increased natural gas demand and caused supply issues due to wellhead freeze-offs, power outages, or other adverse operating conditions upstream of Southwest’s distribution systems. These conditions caused daily natural gas prices to reach unprecedented levels. During this time, Southwest secured natural gas supplies, albeit at substantially higher prices, maintaining service to its customers. The incremental cost for these supplies was approximately $250 million, funded using a 364-day $250 million term loan executed in March 2021. The incremental gas costs were included, for collection from customers, as part of the purchased gas adjustment (“PGA”) mechanisms.
Prepaid and other current assets	Prepaid and other current assets. Prepaid and other current assets for Southwest include, among other things, materials and operating supplies of $60 million at March 31, 2022 and $62.9 million at December 31, 2021 (carried at weighted average cost). For the Company, there were materials and operating supplies of $64.6 million and $67.4 million at March 31, 2022 and December 31, 2021, which included amounts for MountainWest. Also included in the balance for both Southwest and the Company was $52 million as of December 31, 2021 in accrued purchased gas cost, with no corresponding asset balance as of March 31, 2022 for either entity.
Goodwill	Goodwill. Goodwill is assessed as of October 1st each year for impairment, or more frequently, if circumstances indicate an impairment to the carrying value of goodwill may have occurred. Management of the Company and Southwest considered its reporting units and segments, determining that they remained consistent between periods presented below, and that no change was necessary with regard to the level at which goodwill is assessed for impairment. The acquisition of MountainWest resulted in a new reportable segment which is assessed for impairment beginning in 2022.
Other current liabilities	Other Current Liabilities. Management recognizes in its balance sheets various liabilities that are expected to be settled through future cash payment within the next twelve months, including amounts payable under regulatory mechanisms, customary accrued expenses for employee compensation and benefits, declared but unpaid dividends, and miscellaneous other accrued liabilities. Other current liabilities for the Company include $41.4 million and $36 million of dividends declared as of March 31, 2022 and December 31, 2021, respectively.
Earnings Per Share	Earnings Per Share. Basic earnings per share (“EPS”) in each period of this report were calculated by dividing net income attributable to Southwest Gas Holdings, Inc. by the weighted-average number of shares during those periods. Diluted EPS includes additional weighted-average common stock equivalents (performance shares and restricted stock units). Unless otherwise noted, the term “Earnings Per Share” refers to Basic EPS.
Recent Accounting Standards Updates	Recent Accounting Standards Updates. Accounting pronouncements effective or adopted in 2022: In March 2020, the FASB issued ASU 2020-04 “Reference Rate Reform (Topic 848): Facilitation of the Effects of Reference Rate Reform on Financial Reporting.” The update provides optional guidance for a limited time to ease the potential burden in accounting for, or recognizing the effects of, reference rate reform on financial reporting, including when modifying a contract (during the eligibility period covered by the update to Topic 848) to replace a reference rate affected by such reform. The update applies only to contracts and hedging relationships that reference the London Interbank Offered Rate (“LIBOR”) or another rate expected to be discontinued due to reference rate reform. The guidance was eligible to be applied upon issuance on March 12, 2020, and can generally be applied through December 31, 2022, but to date, no further updates have occurred that would extend the optional guidance to the full tenor of LIBOR expiration dates occurring after 2022. Management will monitor the impacts this update might have on the Company’s and Southwest’s consolidated financial statements and disclosures, and will reflect such appropriately, in the event that the optional guidance is elected. Management will also monitor further FASB action, if any, in regard to the full tenor of LIBOR expiration dates. See also LIBOR discussion in Note 5 – Debt. In August 2020, the FASB issued ASU 2020-06 “Debt—Debt with Conversion and Other Options (Subtopic 470-20) and Derivatives and Hedging— Contracts in Entity’s Own Equity (Subtopic 815-40): Accounting for Convertible Instruments and Contracts in an Entity’s Own Equity.” The update, amongst other amendments, improves the guidance related to the disclosures and earnings-per-share for convertible instruments and contracts in an entity’s own equity. The update is effective starting in the first quarter of 2022 in regard to relevant contracts.

Background, Organization, and Summary of Significant Accounting Policies (Policies)

3 Months Ended

Mar. 31, 2022

Organization, Consolidation and Presentation of Financial Statements [Abstract]

Nature of Operations. Southwest Gas Holdings, Inc. (together with its subsidiaries, the “Company”) is a holding company, owning all of the shares of common stock of Southwest Gas Corporation (“Southwest” or the “natural gas distribution” segment), all of the shares of common stock of Centuri Group, Inc. (“Centuri,” or the “utility infrastructure services” segment), and all of the shares of common stock of MountainWest Pipelines Holding Company (“MountainWest,” or the “pipeline and storage” segment).

The Company completed the acquisition of Dominion Energy Questar Pipeline, LLC and related entities (“Questar Pipelines”) in December 2021. Following the completion of the acquisition, the Company formed MountainWest which owns all of the membership interests in Questar Pipelines. In April 2022, the Company completed a general rebranding of the Questar Pipelines entities under the MountainWest name. The acquired operations further diversify the Company’s business in the midstream sector, with an expansion of interstate natural gas pipelines and underground storage services, primarily composed of regulated operations under the jurisdiction of the Federal Energy Regulatory Commission (the “FERC”), thereby expanding natural gas transportation services into Utah, Wyoming, and Colorado. See Note 8 - Business Acquisitions for more information.

Southwest 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 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. Results for the natural gas distribution segment are higher during winter periods due to the seasonality incorporated in its regulatory rate structures.

Centuri is a strategic utility infrastructure services company dedicated to partnering with North America’s gas and electric providers to build and maintain the energy network that powers millions of homes across the United States (“U.S.”) and Canada. Centuri derives revenue primarily from installation, replacement, repair, and maintenance of energy networks. Centuri operates in the U.S., primarily as NPL, Neuco, Linetec, and Riggs Distler, and in Canada, primarily as NPL Canada. Utility infrastructure services activity is seasonal in many of Centuri’s operating areas. Peak periods are the summer and fall months in colder climate areas, such as the northeastern and midwestern U.S. and in Canada. In warmer climate areas, such as the southwestern and southeastern U.S., utility infrastructure services activity continues year round.

Basis of Presentation

Basis of Presentation. The condensed consolidated financial statements of Southwest Gas Holdings, Inc. and subsidiaries and Southwest included herein have been prepared pursuant to the rules and regulations of the Securities and Exchange Commission (the “SEC”). The year-end condensed balance sheet data was derived from audited financial statements. Certain information and footnote disclosures normally included in financial statements prepared in accordance with U.S. generally accepted accounting principles (“U.S. GAAP”) have been condensed or omitted pursuant to such rules and regulations. No substantive change has occurred with regard to the Company’s business segments on the whole.

The preparation of the condensed consolidated financial statements requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities as of the date of the financial statements, and the reported amounts of revenues and expenses during the reporting period. Actual results could differ from those estimates. In the opinion of management, all adjustments, consisting of normal recurring items and estimates necessary for a fair depiction of results for the interim periods, have been made.

These condensed consolidated financial statements should be read in conjunction with the consolidated financial statements and notes thereto included in the 2021 Annual Report to Stockholders, which is incorporated by reference into the 2021 Form 10-K.

Fair Value Measurements

Cash and Cash Equivalents

Cash and Cash Equivalents. Cash and cash equivalents include money market fund investments totaling approximately $169 million and $231 million, for Southwest and the Company, respectively, at March 31, 2022, and $20 million for the Company as of December 31, 2021. The balance for Southwest as of December 31, 2021 was insignificant. These investments fall within Level 2 of the fair value hierarchy, due to the asset valuation methods used by money market funds. The Company had $7 million in restricted cash included in Cash and cash equivalents at March 31, 2022, related to residual proceeds received from its March 2022 common stock offering to be applied against its 364-day Term Loan Facility, which occurred in April 2022. The restricted cash balance is included in Cash and cash equivalents within the Company’s Condensed Consolidated Statement of Cash Flows as of March 31, 2022.Non-cash investing activities for the Company and Southwest include capital expenditures that were not yet paid totaling approximately $26.1 million at March 31, 2022, and $19.4 million at December 31, 2021.

Accounts Receivable, net of allowances

Accounts Receivable, net of allowances. Southwest lifted the moratorium on disconnection of natural gas service for non-payment in Arizona and Nevada in September 2021, which was initiated (at the same time as a moratorium on late fees) in March 2020 in response to the COVID-19 pandemic. The moratorium on disconnection in California ended in November 2021. Southwest recommenced assessing late fees on past-due balances in Arizona and Nevada in April 2021, and in California in August 2021. Southwest continues to actively work with customers experiencing financial hardship by means of flexible payment options, partnering with assistance agencies and participating in state-funded arrearage payment assistance programs.

In mid-February 2021, the central U.S. experienced extreme cold temperatures, which increased natural gas demand and caused supply issues due to wellhead freeze-offs, power outages, or other adverse operating conditions upstream of Southwest’s distribution systems. These conditions caused daily natural gas prices to reach unprecedented levels. During this time, Southwest secured natural gas supplies, albeit at substantially higher prices, maintaining service to its customers. The incremental cost for these supplies was approximately $250 million, funded using a 364-day $250 million term loan executed in March 2021. The incremental gas costs were included, for collection from customers, as part of the purchased gas adjustment (“PGA”) mechanisms. The term loan was amended in March 2022 to extend the maturity date to March 2023 due to gas prices that, while not at levels incurred during the 2021 freeze, continue to be elevated (see Note 5 – Debt).

Deferred Purchased Gas Costs

Deferred Purchased Gas Costs. The various regulatory commissions have established procedures to enable the rate-regulated companies to adjust billing rates for changes in the cost of natural gas purchased. The difference between the current cost of gas purchased and the cost of gas recovered in billed rates is deferred. Generally, these deferred amounts are recovered or refunded within one year. In mid-February 2021, the central U.S. experienced extreme cold temperatures, which increased natural gas demand and caused supply issues due to wellhead freeze-offs, power outages, or other adverse operating conditions upstream of Southwest’s distribution systems. These conditions caused daily natural gas prices to reach unprecedented levels. During this time, Southwest secured natural gas supplies, albeit at substantially higher prices, maintaining service to its customers. The incremental cost for these supplies was approximately $250 million, funded using a 364-day $250 million term loan executed in March 2021. The incremental gas costs were included, for collection from customers, as part of the purchased gas adjustment (“PGA”) mechanisms.

Prepaid and other current assets

Prepaid and other current assets. Prepaid and other current assets for Southwest include, among other things, materials and operating supplies of $60 million at March 31, 2022 and $62.9 million at December 31, 2021 (carried at weighted average cost). For the Company, there were materials and operating supplies of $64.6 million and $67.4 million at March 31, 2022 and December 31, 2021, which included amounts for MountainWest. Also included in the balance for both Southwest and the Company was $52 million as of December 31, 2021 in accrued purchased gas cost, with no corresponding asset balance as of March 31, 2022 for either entity.

Goodwill

Goodwill. Goodwill is assessed as of October 1st each year for impairment, or more frequently, if circumstances indicate an impairment to the carrying value of goodwill may have occurred. Management of the Company and Southwest considered its reporting units and segments, determining that they remained consistent between periods presented below, and that no change was necessary with regard to the level at which goodwill is assessed for impairment. The acquisition of MountainWest resulted in a new reportable segment which is assessed for impairment beginning in 2022.

Other current liabilities

Other Current Liabilities. Management recognizes in its balance sheets various liabilities that are expected to be settled through future cash payment within the next twelve months, including amounts payable under regulatory mechanisms, customary accrued expenses for employee compensation and benefits, declared but unpaid dividends, and miscellaneous other accrued liabilities. Other current liabilities for the Company include $41.4 million and $36 million of dividends declared as of March 31, 2022 and December 31, 2021, respectively.

Earnings Per Share

Earnings Per Share. Basic earnings per share (“EPS”) in each period of this report were calculated by dividing net income attributable to Southwest Gas Holdings, Inc. by the weighted-average number of shares during those periods. Diluted EPS includes additional weighted-average common stock equivalents (performance shares and restricted stock units). Unless otherwise noted, the term “Earnings Per Share” refers to Basic EPS.

Recent Accounting Standards Updates

Recent Accounting Standards Updates.

Accounting pronouncements effective or adopted in 2022:

In March 2020, the FASB issued ASU 2020-04 “Reference Rate Reform (Topic 848): Facilitation of the Effects of Reference Rate Reform on Financial Reporting.” The update provides optional guidance for a limited time to ease the potential burden in accounting for, or recognizing the effects of, reference rate reform on financial reporting, including when modifying a contract (during the eligibility period covered by the update to Topic 848) to replace a reference rate affected by such reform. The update applies only to contracts and hedging relationships that reference the London Interbank Offered Rate (“LIBOR”) or another rate expected to be discontinued due to reference rate reform. The guidance was eligible to be applied upon issuance on March 12, 2020, and can generally be applied through December 31, 2022, but to date, no further updates have occurred that would extend the optional guidance to the full tenor of LIBOR expiration dates occurring after 2022. Management will monitor the impacts this update might have on the Company’s and Southwest’s consolidated financial statements and disclosures, and will reflect such appropriately, in the event that the optional guidance is elected. Management will also monitor further FASB action, if any, in regard to the full tenor of LIBOR expiration dates. See also LIBOR discussion in Note 5 – Debt.

In August 2020, the FASB issued ASU 2020-06 “Debt—Debt with Conversion and Other Options (Subtopic 470-20) and Derivatives and Hedging— Contracts in Entity’s Own Equity (Subtopic 815-40): Accounting for Convertible Instruments and Contracts in an Entity’s Own Equity.” The update, amongst other amendments, improves the guidance related to the disclosures and earnings-per-share for convertible instruments and contracts in an entity’s own equity. The update is effective starting in the first quarter of 2022 in regard to relevant contracts.