CENTURI HOLDINGS, INC., 10-Q filed on 5/8/2024
Quarterly Report
v3.24.1.u1
Cover - shares
 3 Months Ended
Mar. 31, 2024
Apr. 30, 2024
Cover [Abstract]    
Document Type 10-Q  
Document Quarterly Report true  
Document Period End Date Mar. 31, 2024  
Document Transition Report false  
Entity File Number 001-42022  
Entity Registrant Name Centuri Holdings, Inc.  
Entity Incorporation, State or Country Code DE  
Entity Tax Identification Number 93-1817741  
Entity Address, Address Line One 19820 North 7th Avenue  
Entity Address, Address Line Two Suite 120  
Entity Address, City or Town Phoenix  
Entity Address, State or Province AZ  
Entity Address, Postal Zip Code 85027  
City Area Code (623)  
Local Phone Number 582-1235  
Title of 12(b) Security Common stock, $0.01 par value  
Trading Symbol CTRI  
Security Exchange Name NYSE  
Entity Current Reporting Status No  
Entity Interactive Data Current Yes  
Entity Filer Category Non-accelerated Filer  
Entity Small Business false  
Entity Emerging Growth Company false  
Entity Shell Company false  
Entity Common Stock, Shares Outstanding   88,517,521
Current Fiscal Year End Date --12-31  
Entity Central Index Key 0001981599  
Document Fiscal Year Focus 2024  
Document Fiscal Period Focus Q1  
Amendment Flag false  
v3.24.1.u1
Condensed Consolidated Balance Sheets - USD ($)
$ in Thousands
Mar. 31, 2024
Dec. 31, 2023
Current assets:    
Cash and cash equivalents $ 18,405 $ 33,407
Accounts receivable, net 287,815 347,454
Contract assets 257,830 269,808
Prepaid expenses and other current assets 48,951 32,258
Total current assets 613,001 682,927
Property and equipment, net 537,682 545,442
Intangible assets, net 361,911 369,048
Goodwill, net 373,646 375,892
Right-of-use assets under finance leases 41,089 43,525
Right-of-use assets under operating leases 117,827 118,448
Other assets 74,150 54,626
Total assets 2,119,306 2,189,908
Current liabilities:    
Current portion of long-term debt 42,770 42,552
Current portion of finance lease liabilities 11,092 11,370
Current portion of operating lease liabilities 19,940 19,363
Accounts payable 114,613 116,583
Accrued expenses 238,134 187,050
Contract liabilities 13,648 43,694
Total current liabilities 440,197 420,612
Long-term debt, net of current portion 1,021,318 1,031,174
Line of credit 125,229 77,121
Finance lease liabilities, net of current portion 21,670 24,334
Operating lease liabilities, net of current portion 104,110 105,215
Deferred income taxes 134,939 135,123
Other long-term liabilities 69,564 71,076
Total liabilities 1,917,027 1,864,655
Commitments and contingencies (Note 14)
Temporary equity:    
Redeemable noncontrolling interests 4,511 99,262
Equity:    
Common stock, $0.01 par value, 1,000 shares authorized, and 103.52 shares issued and outstanding 0 0
Additional paid-in capital 373,351 374,124
Accumulated other comprehensive loss (6,568) (4,025)
Accumulated deficit (169,015) (144,108)
Total equity 197,768 225,991
Total liabilities, temporary equity and equity 2,119,306 2,189,908
Nonrelated Party    
Current assets:    
Accounts receivable, net 279,406 335,196
Contract assets 254,369 266,600
Related Party    
Current assets:    
Accounts receivable, net 8,409 12,258
Contract assets 3,461 3,208
Current liabilities:    
Contract liabilities $ 0 $ 0
v3.24.1.u1
Condensed Consolidated Balance Sheets (Parenthetical) - $ / shares
Mar. 31, 2024
Dec. 31, 2023
Statement of Financial Position [Abstract]    
Par value (in USD per share) $ 0.01 $ 0.01
Common stock authorized (in shares) 1,000 1,000
Common stock outstanding (in shares) 103.52 103.52
Common stock issued (in shares) 103.52 103.52
v3.24.1.u1
Condensed Consolidated Statements of Operations - USD ($)
$ in Thousands
 3 Months Ended
Mar. 31, 2024
Apr. 02, 2023
Total revenue $ 528,023 $ 653,293
Total cost of revenue 514,744 611,344
Gross profit 13,279 41,949
Selling, general and administrative expenses 28,550 23,539
Amortization of intangible assets 6,668 6,667
Operating (loss) income (21,939) 11,743
Interest expense, net 24,099 22,376
Other (income) expense, net (32) 680
Loss before income tax benefit (46,006) (11,313)
Income tax benefit (20,773) (4,208)
Net loss (25,233) (7,105)
Net (loss) income attributable to redeemable noncontrolling interests (175) 1,739
Net Income (Loss) $ (25,058) $ (8,844)
Loss per share attributable to common stock:    
Basic (in USD per share) $ (242,060) $ (85,433)
Diluted (in USD per share) $ (242,060) $ (85,433)
Shares used in computing earnings per share:    
Weighted average basic shares outstanding (in shares) 100 100
Weighted average diluted shares outstanding (in shares) 100 100
Nonrelated Party    
Total revenue $ 504,745 $ 624,489
Total cost of revenue 492,853 584,115
Related Party    
Total revenue 23,278 28,804
Total cost of revenue 21,891 27,229
Gross profit 1,400 1,600
Selling, general and administrative expenses $ 400 $ 300
v3.24.1.u1
Condensed Consolidated Statements of Comprehensive Income (Loss) - USD ($)
$ in Thousands
 3 Months Ended
Mar. 31, 2024
Apr. 02, 2023
Statement of Comprehensive Income [Abstract]    
Net loss $ (25,233) $ (7,105)
Other comprehensive (loss) income, net of tax:    
Foreign currency translation adjustment (2,543) 87
Other comprehensive (loss) income, net of tax (2,543) 87
Comprehensive loss (27,776) (7,018)
Comprehensive (loss) income attributable to noncontrolling interests (175) 1,739
Total comprehensive loss attributable to common stock $ (27,601) $ (8,757)
v3.24.1.u1
Condensed Consolidated Statements of Cash Flows - USD ($)
$ in Thousands
 3 Months Ended
Mar. 31, 2024
Apr. 02, 2023
Cash flows from operating activities:    
Net loss $ (25,233) $ (7,105)
Adjustments to reconcile net loss to net cash provided by operating activities:    
Depreciation 27,651 31,203
Amortization of intangible assets 6,668 6,667
Amortization related to debt issuance costs 1,318 1,260
Non-cash stock-based compensation expense (588) 144
Gain on sale of equipment (944) (661)
Amortization of right-of-use assets 5,100 3,712
Deferred income taxes (1,600) (5,267)
Changes in assets and liabilities, net of non-cash transactions (34,585) 21,925
Net cash (used in) provided by operating activities (22,213) 51,878
Cash flows from investing activities:    
Capital expenditures (30,499) (23,237)
Proceeds from sale of property and equipment 1,624 2,666
Net cash used in investing activities (28,875) (20,571)
Cash flows from financing activities:    
Proceeds from line of credit borrowings 55,896 8,137
Payment of line of credit borrowings (5,931) (71,017)
Principal payments on long-term debt (10,557) (13,207)
Principal payments on finance lease liabilities (2,914) (3,056)
Redemption of redeemable noncontrolling interest (37) 0
Other (173) (213)
Net cash provided by (used in) financing activities 36,284 (79,356)
Effects of foreign exchange translation (198) 104
Net decrease in cash and cash equivalents (15,002) (47,945)
Cash and cash equivalents, beginning of period 33,407 63,966
Cash and cash equivalents, end of period $ 18,405 $ 16,021
v3.24.1.u1
Condensed Consolidated Statements of Changes in Equity - USD ($)
$ in Thousands
Total
Common Stock
Additional Paid-in Capital
Accumulated Other Comprehensive Loss
Retained Earnings (Accumulated Deficit)
Beginning balance (in shares) at Dec. 31, 2022   103.52      
Beginning balance at Dec. 31, 2022 $ 386,753 $ 0 $ 370,134 $ (6,494) $ 23,113
Net loss (8,844)       (8,844)
Stock-based compensation activity (70)   (25)   (45)
Foreign currency translation adjustment 87     87  
Capital contribution and distribution from related party 670   670    
Noncontrolling interest revaluation (5,832)       (5,832)
Ending balance (in shares) at Apr. 02, 2023   103.52      
Ending balance at Apr. 02, 2023 $ 372,764 $ 0 370,779 (6,407) 8,392
Beginning balance (in shares) at Dec. 31, 2023 103.52 103.52      
Beginning balance at Dec. 31, 2023 $ 225,991 $ 0 374,124 (4,025) (144,108)
Net loss (25,058)       (25,058)
Stock-based compensation activity (761)   (912)   151
Foreign currency translation adjustment (2,543)     (2,543)  
Purchase of noncontrolling interest 4,187   4,187    
Capital contribution and distribution from related party (1,599)   (1,599)    
Noncontrolling interest revaluation $ (2,449)   (2,449)    
Ending balance (in shares) at Mar. 31, 2024 103.52 103.52      
Ending balance at Mar. 31, 2024 $ 197,768 $ 0 $ 373,351 $ (6,568) $ (169,015)
v3.24.1.u1
Description of Business
 3 Months Ended
Mar. 31, 2024
Organization, Consolidation and Presentation of Financial Statements [Abstract]  
Description of Business Description of Business
Centuri Group, Inc. (together with its consolidated subsidiaries, the “Company” or “Centuri”) is a pure-play North American utility infrastructure services company that partners with regulated utilities to maintain, upgrade and expand the energy network that powers millions of homes and businesses. The Company’s service offerings primarily consist of the modernization of utility infrastructure through the maintenance, retrofitting and installation of electric and natural gas distribution networks, building capacity to meet current and future demands and preparing systems for energy transition. The Company operates through a family of integrated companies working together across different geographies leading us to establish solid relationships and a strong reputation for a wide range of capabilities.

Centuri was formed as a wholly owned subsidiary of Southwest Gas Holdings, Inc. (“Southwest Gas Holdings”), which is a publicly traded entity on the New York Stock Exchange.

Centuri Holdings, Inc. (“Holdings”) was incorporated in Delaware in June 2023 as a wholly owned subsidiary of Southwest Gas Holdings. Holdings was formed for the purpose of completing an initial public offering, facilitating the separation of Centuri from Southwest Gas Holdings and other related transactions (as described in “Note 15 – Subsequent Events”) in order to carry on the business of Centuri, the predecessor of Holdings for financial reporting purposes. As of March 31, 2024, and December 31, 2023, Southwest Gas Holdings owned 1,000 shares of Holdings common stock, representing 100% of the issued and outstanding shares of common stock of Holdings. On April 13, 2024, Holdings issued 71,664,592 shares of common stock to Southwest Gas Holdings as consideration for the transfer of assets and assumption of liabilities of Centuri (the “Separation”). Following the completion of the Separation, Centuri became a wholly owned subsidiary of Holdings, and all of Holdings’ operations are conducted through Centuri. On April 17, 2024, the registration statement related to the initial public offering of Holdings’ common stock was declared effective, and Holdings’ common stock began trading on the New York Stock Exchange under the ticker “CTRI” (the “Centuri IPO”) on April 18, 2024.

On April 22, 2024, the Centuri IPO was completed through the sale of 14,260,000 shares of Holdings common stock, par value $0.01 per share, including the underwriters’ full exercise of their option to purchase 1,860,000 shares to cover over-allotments, at an initial public offering price of $21.00 per share. On the same day, Icahn Partners and Icahn Partners Master Fund LP, investment entities affiliated with Carl C. Icahn, purchased 2,591,929 shares of Holdings’ common stock in a concurrent private placement at a price per share equal to the IPO price, for gross proceeds of approximately $54.4 million. The total net proceeds to Holdings from the Centuri IPO and the concurrent private placement, after deducting underwriting discounts and commissions of $18.0 million and estimated offering expenses payable by Holdings, were $329.3 million. As of the closing of the Centuri IPO, Southwest Gas Holdings owned 71,665,592 shares of Holdings common stock, or approximately 81.0% of the total outstanding shares of Holdings.
v3.24.1.u1
Basis of Presentation and Summary of Significant Accounting Policies
 3 Months Ended
Mar. 31, 2024
Accounting Policies [Abstract]  
Basis of Presentation and Summary of Significant Accounting Policies Basis of Presentation and Summary of Significant Accounting Policies
Interim Condensed Consolidated Financial Information
The unaudited condensed consolidated financial statements presented herein are the financial statements of Centuri, the predecessor of Holdings for financial reporting purposes. Holdings had no substantive operations as of March 31, 2024 or December 31, 2023. The unaudited condensed consolidated financial statements and footnotes were prepared in accordance with generally accepted accounting principles in the United States (“GAAP”) for interim financial information and with the instructions to Form 10-Q and Article 10 of Regulation S-X of the U.S. Securities and Exchange Commission (“SEC”). Accordingly, they do not include all of the information and footnotes required by GAAP for complete annual financial statements. Certain information and footnote disclosures, normally included in annual financial statements prepared in accordance with GAAP, have been condensed or omitted pursuant to those rules and regulations. These unaudited condensed consolidated financial statements should be read in conjunction with the Company’s audited consolidated financial statements and the notes thereto for the fiscal year ended December 31, 2023, as included in Holdings’ final IPO prospectus (the “IPO Prospectus”) filed on April 18, 2024 with the SEC pursuant to rule 424(b)(4) under the Securities Act of 1933, as amended relating to Holdings’ Registration Statement on Form S-1. In the opinion of management, all adjustments, consisting only of normal recurring adjustments, necessary to fairly state the financial position, results of operations, comprehensive income and cash flows with respect to the interim condensed consolidated financial statements have been included. The results of operations and comprehensive income for the interim periods are not necessarily indicative of the results for the entire fiscal year. The results of the Company have historically been subject to significant seasonal fluctuations.
As of and prior to December 31, 2023, the Company reported its results under two reportable segments. In January 2024, the Company appointed a new Chief Executive Officer who acts as the Company’s chief operating decision maker (“CODM”). Following the appointment of the Company’s new Chief Executive Officer, the Company underwent an internal personnel reorganization, causing the Company to re-evaluate its reportable segments based on the information reviewed by the new CODM. See “Note 4 — Segment Information” for additional details.

The Company uses a 52/53-week fiscal year that ends on the Sunday closest to the end of the calendar year. Unless otherwise stated, references to months in the Company’s condensed consolidated financial statements relate to fiscal months rather than calendar months. The fiscal three month periods ended March 31, 2024 and April 2, 2023 each had 13 weeks.

Recent Accounting Pronouncements
In November 2023, the Financial Accounting Standards Board (“FASB”) issued Accounting Standards Update (“ASU”) 2023-07, “Segment Reporting (Topic 280): Improvements to Reportable Segment Disclosures.” The update improves reportable segment disclosure requirements, primarily through enhanced disclosures about significant segment expenses. This update is effective beginning with the Company’s 2024 fiscal year annual reporting period, with early adoption permitted. The Company is currently evaluating the impact that the adoption of this update will have on its disclosures.

In December 2023, the FASB issued ASU 2023-09, “Income Taxes (Topic 740): Improvements to Income Tax Disclosures.” The update enhances income tax disclosure requirements. This update is effective beginning with the Company’s 2025 fiscal year annual reporting period, with early adoption permitted. The Company is currently evaluating the impact that the adoption of this update will have on its disclosures.

In March 2024, the SEC issued the final rules under SEC Release No. 33-11275, “The Enhancement and Standardization of Climate-Related Disclosures for Investors.” In April 2024, the SEC voluntarily stayed the new rules as a result of pending legal challenges. Absent the stay and the result of pending legal challenges, these rules will require registrants to disclose certain climate-related information, including Scope 1 and Scope 2 greenhouse gas emissions and other climate-related topics, in registration statements and annual reports, when material. Disclosure requirements, absent the results of pending legal challenges, will begin phasing in with the annual reporting for the fiscal year ending 2027 based on Holdings’ current status as a non-accelerated filer. The Company is currently evaluating the impact the rules will have on its disclosures.
v3.24.1.u1
Revenue and Related Balance Sheet Accounts
 3 Months Ended
Mar. 31, 2024
Revenue from Contract with Customer [Abstract]  
Revenue and Related Balance Sheet Accounts Revenue and Related Balance Sheet Accounts
The following table presents the Company’s revenue from contracts with customers disaggregated by contract type (in thousands):
Fiscal Three Months Ended
March 31, 2024April 2, 2023
Contract Type:
Master services agreements$443,242 $547,606 
Bid contracts84,781 105,687 
Total revenue$528,023 $653,293 
Unit-price contracts$307,849 $328,527 
Time and materials contracts109,892 157,851 
Fixed-price contracts110,282 166,915 
Total revenue$528,023 $653,293 
Contract assets and liabilities consisted of the following (in thousands):
March 31,
2024		December 31,
2023
Current contract assets$257,830 $269,808 
Non-current contract assets16,484 214 
Contract assets, total274,314 270,022 
Contract liabilities(13,648)(43,694)
Net contract assets$260,666 $226,328 
Contract assets primarily consist of revenue earned on contracts in progress in excess of billings, which relates to the Company’s rights to consideration for work completed but not billed and/or approved at the reporting date as well as contract retention balances. Contract assets that are expected to be recognized more than one year from the financial statement date are included in other assets on the condensed consolidated balance sheets. Revenue earned on contracts in progress in excess of billings are transferred to accounts receivable when the rights become unconditional.
Total contract assets increased $4.3 million during the fiscal three months ended March 31, 2024 due primarily to timing of billings. Contract assets are recoverable from the Company’s customers based upon various measures of performance, including achievement of certain milestones, completion of specified units or completion of a contract. In addition, many of the Company’s time and materials (“T&M”) contract arrangements are billed in arrears pursuant to contract terms that are standard within the industry, resulting in revenue earned on contracts in progress in excess of billings and/or unbilled receivables being recorded as revenue is recognized in advance of billings. The lag in billing due to the aforementioned contractual provisions may create circumstances in which material changes to a customer’s business, cash flows or financial condition, which may be impacted by negative economic or market conditions, could affect the Company’s ability to bill and subsequently collect amounts due. These changes may result in the need to record an estimate of the amount of loss from uncollectible receivables.

Contract liabilities primarily consist of amounts billed in excess of revenue earned related to the advance consideration received from customers for which work has not yet been completed. The change in the contract liability balance of $30.0 million from December 31, 2023 to March 31, 2024 was due primarily to revenue recognized that was included in the balance as of December 31, 2023, after which time it became earned and the balance was ultimately realized.
The Company considers retention and unbilled amounts to customers to be conditional contract assets, as payment is contingent on the occurrence of a future event. Accounts receivable, net, includes only amounts that are unconditional in nature, which means only the passage of time remains and the Company has invoiced the customer. Similarly, contract liabilities include amounts billed in excess of revenue earned on contracts in progress related to fixed-price, unit-price and T&M contracts. In the event contract assets or contract liabilities are expected to be recognized more than one year from the financial statement date, the Company classifies those amounts as long-term contract assets or contract liabilities, included in other assets or other long-term liabilities, respectively, on the condensed consolidated balance sheets.
For contracts with an original duration of one year or less, the Company uses the practical expedient applicable to such contracts and does not consider the time value of money. Further, because of the short duration of these contracts, the Company has not disclosed the transaction price for the remaining performance obligations as of the end of each reporting period or the related timing of revenue recognition.
As of March 31, 2024, the Company had 53 fixed-price contracts with an original duration of more than one year. The aggregate amount of the transaction price allocated to the unsatisfied performance obligations of these contracts as of March 31, 2024 was $276.8 million. The Company expects to recognize the remaining performance obligations of these contracts over approximately the next two years; however, the timing of that recognition is largely within the control of the customer, including when the necessary equipment and materials required to complete the work will be provided by the customer.
Accounts receivable, net consisted of the following (in thousands): 
March 31,
2024		December 31,
2023
Billed on completed contracts and contracts in progress$285,896 $348,021 
Other receivables1,989 1,945 
Accounts receivable, gross287,885 349,966 
Allowance for doubtful accounts(70)(2,512)
Accounts receivable, net$287,815 $347,454 
v3.24.1.u1
Segment Information
 3 Months Ended
Mar. 31, 2024
Segment Reporting [Abstract]  
Segment Information Segment Information
As of and prior to December 31, 2023, the Company reported its results under the following two reportable segments: Gas Utility Services and Electric Utility Services. In January 2024, the Company appointed a new Chief Executive Officer who acts as the Company’s CODM. Following the appointment of the Company’s new Chief Executive Officer, the Company underwent an internal personnel reorganization, causing the Company to re-evaluate its reportable segments based on the information reviewed by the new CODM. The Company determined that it was appropriate to re-align its reporting structure from the following two reportable segments: (i) Gas Utility Services; and (ii) Electric Utility Services, to the following four reportable segments: (i) U.S. Gas Utility Services (“U.S. Gas”); (ii) Canadian Gas Utility Services (“Canadian Gas”); (iii) Union Electric Utility Services (“Union Electric”); and (iv) Non-Union Electric Utility Services (“Non-Union Electric”). The U.S. Gas and Canadian Gas businesses have historically been part of the Gas Utility Services segment, and the Union Electric and Non-Union Electric businesses have historically been part of the Electric Utility Services segment. All prior year segment financial information has been recast to reflect the new segment structure.
U.S. Gas
U.S. Gas provides comprehensive services, including maintenance, repair and installation for local natural gas distribution utilities (“LDCs”) throughout the United States focused on the modernization of customers’ infrastructure. The work performed within this segment includes solutions for all stages of utility work and is performed primarily within the distribution, urban transmission and end-user infrastructure rather than large-scale, project-based, cross-country transmission. The Company is able to cater to the needs of its gas utility services customers by serving union and non-union markets.
Canadian Gas
Canadian Gas provides comprehensive services, including maintenance, repair and installation for LDCs focused on the modernization of customers’ infrastructure. The work performed within this segment includes solutions for all stages of utility work and is performed primarily within the distribution, urban transmission and end-user infrastructure rather than large-scale, project-based, cross-country transmission. Canadian Gas serves union markets.
Union Electric
Union Electric provides a comprehensive set of electric utility services encompassing maintenance, repair, upgrade and expansion services for urban transmission and local distribution infrastructure within union markets. The work is focused primarily on recurring local distribution and urban transmission services under master service agreements (“MSAs”) as opposed to large-scale, project-based, cross-country transmission, and services are primarily focused on infrastructure between the substation and end-user meter.
Non-Union Electric
Non-Union Electric provides a comprehensive set of electric utility services encompassing maintenance, repair, upgrade and expansion services for urban transmission and local distribution infrastructure within non-union markets. The work is focused almost exclusively on recurring local distribution and urban transmission services under MSAs as opposed to large-scale, project-based, cross-country transmission, and services are primarily focused on infrastructure between the substation and end-user meter.
Other
Other primarily consists of corporate and non-allocated costs, including corporate facility costs, non-allocated corporate salaries, benefits and incentive compensation. Other also includes certain industrial service activities that do not meet the criteria of a reportable segment.
Revenue and gross profit by segment was as follows (in thousands):
Fiscal Three Months Ended
March 31, 2024April 2, 2023
Revenue:
U.S. Gas$226,578 $259,337 
Canadian Gas34,648 39,303 
Union Electric163,851 205,669 
Non-Union Electric96,615 136,606 
Other6,331 12,378 
Consolidated revenue, net$528,023 $653,293 
Gross profit:
U.S. Gas$(3,976)$3,366 
Canadian Gas5,545 4,476 
Union Electric11,369 15,209 
Non-Union Electric2,800 18,487 
Other(2,459)411 
Consolidated gross profit$13,279 $41,949 
Depreciation expense, included in cost of revenue, by segment was as follows (in thousands):
Fiscal Three Months Ended
March 31, 2024April 2, 2023
U.S. Gas$11,586 $11,678 
Canadian Gas1,506 1,409 
Union Electric6,715 9,449 
Non-Union Electric6,604 7,425 
Other87 75 
Consolidated depreciation expense (1)
$26,498 $30,036 
(1)Depreciation expense within selling, general and administrative expense for each of the fiscal quarters ended March 31, 2024 and April 2, 2023 was $1.2 million and was excluded from the table above as it is not produced or utilized by management to evaluate segment performance.
Separate measures of the Company’s assets and cash flows, with the exception of capital expenditures, are not produced or utilized by management to evaluate segment performance.
Capital expenditures by segment were as follows (in thousands):
Fiscal Three Months Ended
March 31, 2024April 2, 2023
U.S. Gas$14,278 $14,906 
Canadian Gas2,990 1,835 
Union Electric4,193 4,538 
Non-Union Electric4,697 530 
Other4,341 1,428 
Consolidated capital expenditures$30,499 $23,237 
Foreign Operations
During the fiscal three months ended March 31, 2024 and April 2, 2023, the Company recorded revenue of $41.0 million and $51.7 million, respectively, in Canada, which comprised 8% of total revenue in each of the two periods.
v3.24.1.u1
Noncontrolling Interests
 3 Months Ended
Mar. 31, 2024
Temporary Equity Disclosure [Abstract]  
Noncontrolling Interests Noncontrolling Interests
In connection with the acquisition of Linetec Services, LLC (“Linetec”) in November 2018, the previous owner initially retained a 20% equity interest in that entity, the reduction of which was subject to certain rights based on the passage of time or upon the occurrence of certain triggering events. Effective January 2022, the Company had the right, but not the obligation, to purchase at fair value (subject to a floor) a portion of the interest held by the previous owner and in incremental amounts each year thereafter. In March 2022, the parties agreed to a partial redemption based on these provisions, reducing the noncontrolling interest to 15%, and in March 2023, agreed to a partial 5% redemption (of the then 15% remaining), reducing the noncontrolling interest to 10%. In March 2024, the parties entered into an agreement to redeem the remaining 10% equity interest for $92.0 million, which resulted in the Company owning all of the equity interest in Linetec as of March 31, 2024. The Company paid the $92.0 million in April, in accordance with the agreement. The impact of this transaction has been excluded from the Company’s condensed consolidated statement of cash flows for the first quarter of 2024 due to its non-cash nature during the period.

Furthermore, certain members of Riggs Distler & Company, Inc. (“Riggs Distler”) management have a noncontrolling interest in the parent company of Riggs Distler, Drum Parent LLC (formerly Drum Parent, Inc.) (“Drum”) which was 1.41% as of December 31, 2023. This noncontrolling interest is redeemable, subject to certain rights based on the passage of time or upon the occurrence of certain triggering events. A portion of the redeemable noncontrolling interest was funded through promissory notes made to noncontrolling interest holders bearing interest at the prime rate plus 2%.

During the first quarter of 2024, the Company forgave all outstanding promissory notes and unpaid interest owed from the Riggs Distler noncontrolling interest holders and in exchange obtained the 0.47% portion of equity interest in Drum that had been funded through these notes. Additionally, during the first quarter of 2024, the Company reached agreement to purchase a 0.13% noncontrolling interest in Drum for $0.8 million, the majority of which was accrued in March 2024 and ultimately paid in April 2024. The impact of these accrued purchases has been excluded from the Company’s condensed consolidated statement of cash flows for the first quarter of 2024 due to their non-cash nature during the period. The remaining noncontrolling interest in Drum outstanding as of March 31, 2024 was 0.81%.

Significant changes in the value of the redeemable noncontrolling interests, above a floor determined at the establishment date, are recognized as they occur, and the carrying value is adjusted as necessary at each reporting date. The fair value is estimated using a market approach that utilizes certain financial metrics from guideline public companies of similar industry and operating characteristics. Based on the fair value model employed, the estimated redemption value of the Linetec redeemable noncontrolling interest increased by $0.2 million during the first fiscal quarter of 2024 to the value at which it was redeemed. The estimated redemption value of the Riggs Distler redeemable noncontrolling interest increased by $2.3 million during the first fiscal quarter of 2024.
Adjustments to the redemption values have historically impacted retained earnings, as reflected on the condensed consolidated statements of changes in equity. As the Company was in an accumulated deficit position prior to any redemption value adjustment for the first fiscal quarter of 2024, the redemption value adjustments in the quarter decreased the Company’s additional paid in capital.

The following table depicts changes to the balance of the redeemable noncontrolling interests (in thousands):

Linetec
Services, LLC		Drum Parent
LLC		Redeemable
Noncontrolling
Interests
Balance as of December 31, 2023$91,979 $7,283 $99,262 
Net (loss) income attributable to redeemable noncontrolling interests(193)18 (175)
Redemption value adjustment193 2,256 2,449 
Redeemable noncontrolling interests redeemed(91,979)(5,046)(97,025)
Balance as of March 31, 2024$- $4,511 $4,511 
v3.24.1.u1
Goodwill and Intangible Assets
 3 Months Ended
Mar. 31, 2024
Goodwill and Intangible Assets Disclosure [Abstract]  
Goodwill and Intangible Assets Goodwill and Intangible Assets
During fiscal 2024, the Company changed its reporting units to align with changes in its organization structure, and as a result, the Company’s reporting units are the same as its reportable segments. Prior to and after the reporting unit
restructure, the Company qualitatively assessed its reporting units for potential goodwill impairment, and with the exception of Riggs Distler (which was impaired in the fourth fiscal quarter of 2023), the results of the qualitative assessments did not indicate that it was more likely than not that the fair value of each reporting unit analyzed was less than the carrying value including goodwill, and no goodwill impairment was recognized.

Changes in the carrying amount of goodwill of each of the Company’s reportable segments were as follows (in thousands):

U.S. Gas
Canadian Gas
Union Electric (1)
Non-Union ElectricTotal
Balances as of December 31, 2023$58,160 $93,911 $56,499 $167,322 $375,892 
Effect of exchange rate changes- (2,246)- - (2,246)
Balances as of March 31, 2024$58,160 $91,665 $56,499 $167,322 $373,646 
(1) Net of accumulated impairment of $391.1 million as of March 31, 2024 and December 31, 2023.
Goodwill and related accumulated impairment associated with reporting units that do not meet the quantitative thresholds for separate reporting were $10.8 million, resulting in a net carrying value of $0 as of March 31, 2024 and December 31, 2023.
Amortization expense for definite-lived intangible assets was $6.7 million for each of the fiscal three month periods ended March 31, 2024 and April 2, 2023
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Property and Equipment
 3 Months Ended
Mar. 31, 2024
Property, Plant and Equipment [Abstract]  
Property and Equipment Property and Equipment
Property and equipment consisted of the following (in thousands):
March 31,
2024		December 31,
2023
Property and equipment, gross$1,120,661 $1,118,202 
Accumulated depreciation(582,979)(572,760)
Property and equipment, net$537,682 $545,442 
Depreciation expense was $27.7 million and $31.2 million for the fiscal three months ended March 31, 2024 and April 2, 2023, respectively.
The Company recognized gains on the disposition of property and equipment of $0.9 million and $0.7 million for the fiscal three months ended March 31, 2024 and April 2, 2023, respectively.
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Accrued Expenses and Other Current Liabilities
 3 Months Ended
Mar. 31, 2024
Payables and Accruals [Abstract]  
Accrued Expenses and Other Current Liabilities Accrued Expenses and Other Current Liabilities
Accrued expenses and other current liabilities consisted of the following (in thousands):
March 31,
2024		December 31,
2023
Accrued redemption of noncontrolling interests$92,801 $— 
Accrued compensation58,927 92,205 
Accrued expenses50,181 55,186 
Accrued insurance23,777 21,794 
Book overdrafts8,141 13,300 
Accrued taxes3,345 3,590 
Accrued interest962 975 
Accrued expenses and other current liabilities$238,134 $187,050 
v3.24.1.u1
Long-Term Debt
 3 Months Ended
Mar. 31, 2024
Debt Disclosure [Abstract]  
Long-Term Debt Long-Term Debt
Long-term debt, including outstanding amounts on the Company’s line of credit, consisted of the following (in thousands):
March 31, 2024December 31, 2023
Carrying
Amount
Fair Value (1)
Carrying
Amount
Fair Value (1)
Borrowings under revolving line of credit$125,229 $125,324 $77,121 $77,205 
Term loans under loan facility991,375 991,375 994,238 996,723 
Total loan facility1,116,604 1,116,699 1,071,359 1,073,928 
Equipment loans:
2.30%, due May 2025
4,763 4,655 5,768 5,618 
1.75%, due March 2027
6,654 6,256 7,193 6,740 
1.75%, due March 2027
15,526 14,597 16,783 15,727 
2.96%, due March 2027
15,441 14,760 16,667 15,903 
3.27%, due March 2027
18,587 17,855 20,055 19,237 
3.40%, due March 2027
9,304 8,948 10,037 9,641 
3.51%, due March 2027
18,630 17,952 20,096 19,342 
Total long-term debt1,205,509 $1,201,722 1,167,958 $1,166,136 
Current portion of long-term debt(42,770)(42,552)
Unamortized discount and debt issuance costs(16,192)(17,111)
Long-term debt, net of current portion$1,146,547 $1,108,295 
(1)Fair values as of March 31, 2024 and December 31, 2023 were determined using the Company’s credit rating.
On August 27, 2021, the Company entered into an amended and restated credit agreement. The agreement provided for a $1.145 billion secured term loan facility, at a discount of 1.00%, and a $400 million secured revolving credit facility, which in addition to funding the Riggs Distler acquisition, refinanced the Company’s previous $590 million loan facility. This multi-currency facility allows the Company to request loan advances in either Canadian dollars or U.S. dollars. Amounts borrowed and repaid under the revolving line of credit portion of the facility are available to be re-borrowed. The obligations under the credit agreement are secured by present and future ownership interests in substantially all direct and indirect subsidiaries of the Company, substantially all of the tangible and intangible personal property of each borrower, certain of their direct and indirect subsidiaries, and all products, profits, and proceeds of the foregoing. The Company’s assets securing the facility as of March 31, 2024 totaled $2.0 billion. The credit agreement also contains a restriction on dividend payments with a calculated available amount generally defined as 50% of the Company’s rolling twelve-month consolidated net income adjusted for certain items, such as parent capital contributions, redeemable noncontrolling interest payments, dividend payments, among other adjustments, as applicable. The term loan facility matures on August 27, 2028, and the revolving credit facility matures on August 27, 2026.
On May 31, 2023, the Company entered into an amendment to the amended and restated credit agreement to transition the interest rate benchmark for the term loan facility from London Interbank Offered Rate (“LIBOR”) to Secured Overnight Financing Rate (“SOFR”) benchmarks. The applicable margins for the term loan facility remained 1.50% for base rate loans and are 2.50% for SOFR loans. Furthermore, the Company’s Canadian entities may borrow under the revolving credit facility with interest rates based on either a “base rate” or the Canadian Dealer Offered Rate (“CDOR”) plus the applicable margin, at the borrower’s option. The weighted average interest rate on the term loan facility was 7.94% and 7.97% as of March 31, 2024 and December 31, 2023, respectively.
On November 4, 2022, November 13, 2023, and March 22, 2024, the Company amended the financial covenants of the revolving credit facility. Under the amended terms of the revolving credit facility, the Company is required to maintain a net leverage ratio of less than a maximum of 5.75 to 1.00 from January 1, 2024 through March 31, 2024, 6.00 to 1.00 from April 1, 2024 through June 30, 2024, 5.75 to 1.00 from July 1, 2024 through September 29, 2024, 5.00 to 1.00 from September 30, 2024 through December 29, 2024, and 4.00 to 1.00 thereafter. The amended terms of the revolving credit facility also provide that, in the event that a “Qualified IPO” (as defined therein) is consummated prior to March 31, 2025, the maximum net leverage ratio financial covenant will be reduced based on the amount of net proceeds received from such Qualified IPO. Under the amended terms of the revolving credit facility, the Company is required to maintain an interest coverage ratio of greater than a minimum of 2.00 to 1.00 from January 1, 2024 through December 29, 2024, and 2.50 to 1.00 thereafter. As of March 31, 2024, the Company was in compliance with all of the financial covenants under the revolving credit facility. The November 4, 2022 amendment to the amended and restated credit agreement increased a letter of credit sub-facility from $100 million to $125 million, and also transitioned the interest rate benchmark for the revolving
credit facility from LIBOR to SOFR benchmarks. The applicable margin for the revolving credit facility now ranges from 1.0% to 2.5% for SOFR loans and from 0.0% to 1.5% for CDOR and “base rate” loans, depending on the Company’s net leverage ratio. The Company is also required to pay a commitment fee on the unused portion of the commitments which ranges from 0.15% to 0.35% per annum, depending on the Company’s net leverage ratio. The weighted average interest rate on the revolving credit facility was 8.01% and 7.66% as of March 31, 2024 and December 31, 2023, respectively.

As of March 31, 2024 and December 31, 2023, the Company had borrowings outstanding of $1.1 billion under its amended and restated credit agreement. The amount available under the revolving line of credit is further reduced by the amount of any outstanding letters of credit issued by the Company. Accordingly, there was $201.5 million, net of outstanding letters of credit, available to the Company on the revolving line of credit as of March 31, 2024. The Company had $51.7 million and $48.6 million of unused letters of credit available as of March 31, 2024 and December 31, 2023, respectively. Debt issuance costs associated with the Company’s line of credit are amortized over the term of the related line of credit. As of March 31, 2024 and December 31, 2023, there was $4.3 million and $4.2 million, respectively, recorded in other assets on the condensed consolidated balance sheets.
Debt issuance costs associated with the Company’s term loan are amortized over the term of the related debt, which approximates the effective interest method. As of March 31, 2024 and December 31, 2023, debt issuance costs of $16.2 million and $17.1 million, respectively, were recorded as a reduction to long-term debt on the condensed consolidated balance sheets.
Amortization expense related to debt issuance costs is recorded as a component of interest expense in the condensed consolidated statements of operations. During each of the first fiscal three month periods of 2024 and 2023, amortization of debt issuance costs was $1.3 million.
The Company currently has seven equipment term loans with initial amounts totaling approximately $170 million, with certain owned equipment used as collateral. The loans are serviced in U.S. dollars. These term loans have prepayment penalties for the first three years of the agreements. The Company did not incur any prepayment penalties on any these equipment loans during the first fiscal three months of 2024 or 2023.
The fair value of the Company’s debt as of March 31, 2024 and December 31, 2023 was $1.2 billion. The fair value of the Company’s revolving credit facility is categorized as Level 1 based on the fair value hierarchy, due to the Company’s ability to access similar debt arrangements at measurement dates with comparable terms, including variable/market rates. The fair values of the Company’s term loan facility and equipment loans were determined utilizing a market-based valuation approach, where fair values are determined based on evaluated pricing data, and as such are categorized as Level 2 in the hierarchy.
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Leases
 3 Months Ended
Mar. 31, 2024
Leases [Abstract]  
Leases Leases
The Company has operating and finance leases for corporate and field offices, construction equipment and transportation vehicles. The Company is currently not a lessor in any significant lease arrangements. The Company’s leases have remaining lease terms of up to 15 years. Some of these leases include options to extend the leases, generally for optional terms of up to five years, and some include options to terminate the leases within one year. The equipment leases may include variable payment terms in addition to the fixed lease payments if machinery is used in excess of the standard work periods. These variable payments are not probable of occurring under the Company’s current operating environment and have not been included in consideration of lease payments. Leases with an initial term of 12 months or less are classified as short-term leases and are not recognized on the condensed consolidated balance sheets unless the lease contains a purchase option that is reasonably certain to be exercised, or unless it is reasonably certain that the equipment will be leased for greater than 12 months. Due to the seasonality of the Company’s operations, expense for short-term leases will fluctuate throughout the year with higher expense typically incurred during the periods when revenue is the greatest. As of March 31, 2024, the Company did not have any significant executed lease agreements that had not yet commenced.
The components of lease expense were as follows (in thousands):
Fiscal Three Months Ended
Lease costClassificationMarch 31, 2024April 2, 2023
Operating lease costCost of revenue and selling, general and administrative expenses$6,631 $4,772 
Finance lease cost:
Amortization of ROU assets
Depreciation (1)
2,112 1,592 
Interest on lease liabilitiesInterest expense, net365 448 
Total finance lease cost2,477 2,040 
Short-term lease cost (2)
Cost of revenue and selling, general and administrative expenses21,260 28,437 
Total lease cost$30,368 $35,249 
(1)Depreciation is included within cost of revenue in the accompanying condensed consolidated statements of operations.
(2)Short-term lease cost includes both leases and rentals with initial terms of 12 months or less.
Supplemental cash flow information related to leases was as follows (in thousands):
Fiscal Three Months Ended
March 31, 2024April 2, 2023
Cash paid for amounts included in the measurement of lease liabilities:
Operating cash flows from operating leases$6,569 $4,509 
Operating cash flows from finance leases365 448 
Financing cash flows from finance leases2,914 3,056 
Right-of-use assets obtained in exchange for lease obligations:
Operating leases$4,904 $17,929 
Finance leases— 1,001 
Supplemental information related to leases was as follows:
March 31,
2024		December 31,
2023
Weighted average remaining lease term (in years):
Operating leases7.197.45
Finance leases3.473.64
Weighted average discount rate:
Operating leases4.96 %4.88 %
Finance leases4.07 %4.02 %
The following is a schedule of maturities of lease liabilities as of March 31, 2024 (in thousands):
Operating
Leases		Finance
Leases
Fiscal year ended:
Remainder of 2024$19,461 $9,386 
202522,905 10,233 
202620,497 7,646 
202719,061 5,756 
202816,645 1,727 
Thereafter49,076 748 
Total lease payments147,645 35,496 
Less: Amount of lease payments representing interest(23,595)(2,734)
Total$124,050 $32,762 
Certain leases require the Company to pay variable property taxes, insurance and maintenance costs that have been excluded from the minimum lease payments in the above tables as they are variable in nature.
Leases Leases
The Company has operating and finance leases for corporate and field offices, construction equipment and transportation vehicles. The Company is currently not a lessor in any significant lease arrangements. The Company’s leases have remaining lease terms of up to 15 years. Some of these leases include options to extend the leases, generally for optional terms of up to five years, and some include options to terminate the leases within one year. The equipment leases may include variable payment terms in addition to the fixed lease payments if machinery is used in excess of the standard work periods. These variable payments are not probable of occurring under the Company’s current operating environment and have not been included in consideration of lease payments. Leases with an initial term of 12 months or less are classified as short-term leases and are not recognized on the condensed consolidated balance sheets unless the lease contains a purchase option that is reasonably certain to be exercised, or unless it is reasonably certain that the equipment will be leased for greater than 12 months. Due to the seasonality of the Company’s operations, expense for short-term leases will fluctuate throughout the year with higher expense typically incurred during the periods when revenue is the greatest. As of March 31, 2024, the Company did not have any significant executed lease agreements that had not yet commenced.
The components of lease expense were as follows (in thousands):
Fiscal Three Months Ended
Lease costClassificationMarch 31, 2024April 2, 2023
Operating lease costCost of revenue and selling, general and administrative expenses$6,631 $4,772 
Finance lease cost:
Amortization of ROU assets
Depreciation (1)
2,112 1,592 
Interest on lease liabilitiesInterest expense, net365 448 
Total finance lease cost2,477 2,040 
Short-term lease cost (2)
Cost of revenue and selling, general and administrative expenses21,260 28,437 
Total lease cost$30,368 $35,249 
(1)Depreciation is included within cost of revenue in the accompanying condensed consolidated statements of operations.
(2)Short-term lease cost includes both leases and rentals with initial terms of 12 months or less.
Supplemental cash flow information related to leases was as follows (in thousands):
Fiscal Three Months Ended
March 31, 2024April 2, 2023
Cash paid for amounts included in the measurement of lease liabilities:
Operating cash flows from operating leases$6,569 $4,509 
Operating cash flows from finance leases365 448 
Financing cash flows from finance leases2,914 3,056 
Right-of-use assets obtained in exchange for lease obligations:
Operating leases$4,904 $17,929 
Finance leases— 1,001 
Supplemental information related to leases was as follows:
March 31,
2024		December 31,
2023
Weighted average remaining lease term (in years):
Operating leases7.197.45
Finance leases3.473.64
Weighted average discount rate:
Operating leases4.96 %4.88 %
Finance leases4.07 %4.02 %
The following is a schedule of maturities of lease liabilities as of March 31, 2024 (in thousands):
Operating
Leases		Finance
Leases
Fiscal year ended:
Remainder of 2024$19,461 $9,386 
202522,905 10,233 
202620,497 7,646 
202719,061 5,756 
202816,645 1,727 
Thereafter49,076 748 
Total lease payments147,645 35,496 
Less: Amount of lease payments representing interest(23,595)(2,734)
Total$124,050 $32,762 
Certain leases require the Company to pay variable property taxes, insurance and maintenance costs that have been excluded from the minimum lease payments in the above tables as they are variable in nature.
v3.24.1.u1
Income Taxes
 3 Months Ended
Mar. 31, 2024
Income Tax Disclosure [Abstract]  
Income Taxes Income Taxes
The Company’s quarterly provision for income taxes was prepared using the effective annual tax rate adjusted to remove discrete items, as those items will impact the quarter in which those items were reflected. The Company’s effective tax rate for the fiscal three months ended March 31, 2024 and April 2, 2023 was 45.2% and 37.2%, respectively. The change in effective rates during each of the respective periods was primarily due to pre-tax income/loss differences by jurisdiction and for changes in permanent differences.
The Company regularly evaluates valuation allowances established for deferred tax assets for which future realization is uncertain, including in connection with changes in tax laws. The Company maintains a valuation allowance on certain state net operating loss carryforwards. Such valuation allowances are released as the related tax benefits are realized or when sufficient evidence exists to conclude that it is more likely than not the deferred tax assets will be realized.

As of March 31, 2024 and December 31, 2023, the total amount of unrecognized tax benefits relating to uncertain tax positions was $0.5 million.
As of March 31, 2024, with certain exceptions, the Company is no longer subject to U.S. federal, state, local, or Canadian examinations for years before fiscal 2018. The Company is a party to a tax sharing agreement with Southwest Gas Holdings. The agreement outlines the method in which the Company calculates its income tax liability and the manner in which it either reimburses Southwest Gas Holdings for taxes owed or is reimbursed for credits and net operating losses used. See “Note 13 — Related Parties” for more information. Note that this tax sharing agreement was superseded by the tax matters agreement signed by Holdings and Southwest Gas Holdings on April 11, 2024. Refer to “Note 15 — Subsequent Events” for more information.
v3.24.1.u1
Supplemental Cash Flow Disclosures
 3 Months Ended
Mar. 31, 2024
Organization, Consolidation and Presentation of Financial Statements [Abstract]  
Supplemental Cash Flow Disclosures Supplemental Cash Flow Disclosures
The following table represents the Company’s supplemental cash flow disclosures and non-cash investing activity, excluding lease activity (which is disclosed in “Note 10 — Leases”) (in thousands):
March 31,
2024		April 2,
2023
Non-cash investing activities:
Accrued capital expenditures$3,945 $4,011 
Proceeds from sale of property and equipment in accounts receivable599 441 
As of March 31, 2024, the Company had accrued $92.8 million in connection with redemptions of noncontrolling interests at Linetec and Riggs Distler, the impact of which has been excluded from the Company’s condensed consolidated statement of cash flows for the first quarter of 2024 due to the non-cash nature of these transactions during the period. Refer to “Note 5 — Noncontrolling Interests” for additional details.
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Related Parties
 3 Months Ended
Mar. 31, 2024
Related Party Transactions [Abstract]  
Related Parties Related Parties
The Company performs various construction services for Southwest Gas Corporation, a wholly owned subsidiary of Southwest Gas Holdings. Approximately $23.3 million (4%) and $28.8 million (4%) of the Company’s revenue for the fiscal three months ended March 31, 2024 and April 2, 2023, respectively, was related to contracts with Southwest Gas Corporation. The Company recognized gross profit related to the Southwest Gas Corporation revenue of $1.4 million (11%) and $1.6 million (4%) for the fiscal three months ended March 31, 2024 and April 2, 2023, respectively. As of March 31, 2024 and December 31, 2023, approximately $8.4 million (3%) and $12.3 million (4%), respectively, of the Company’s accounts receivable, and $3.5 million and $3.2 million, respectively, of contract assets were related to contracts with Southwest Gas Corporation. There were no significant related party contract liabilities as of March 31, 2024 or December 31, 2023 with Southwest Gas Corporation.
Additionally, certain costs incurred by Southwest Gas Holdings have been allocated to Centuri, which are settled in cash during the normal course of operations. For the fiscal three months ended March 31, 2024 and April 2, 2023, the Company recorded $0.4 million and $0.3 million of allocated costs, respectively. These costs are recorded within selling, general and administrative expenses on the Company’s condensed consolidated statements of operations.
The Company is party to a tax sharing agreement with Southwest Gas Holdings. The agreement outlines the method in which the Company calculates its income tax liability and the manner in which it either reimburses Southwest Gas Holdings for taxes owed or is reimbursed for credits and net operating losses used. As of March 31, 2024 and December 31, 2023, there were no amounts due to or from Southwest Gas Holdings.

As discussed in “Note 15 — Subsequent Events,” the Company became party to a number of agreements with Southwest Gas Holdings on April 11, 2024 governing the relationship of the Company and Southwest Gas Holdings subsequent to the Separation and Centuri IPO.
In November 2021, certain members of Riggs Distler management acquired a 1.42% interest in Drum. See “Note 5 — Noncontrolling Interests” for more information. A portion of the redeemable noncontrolling interest acquired was funded through promissory notes made to noncontrolling interest holders bearing interest at the prime rate plus 2%. The promissory notes are payable by the noncontrolling interest holders upon certain triggering events, including, but not limited to, termination of employment or the redemption of any interest under the agreement. The promissory notes and related interest income are recorded in additional paid-in capital, a component of total equity, on the condensed consolidated balance sheets. During the first quarter of 2024, the Company forgave all outstanding promissory notes and unpaid interest owed from the Riggs Distler noncontrolling interest holders and in exchange obtained the 0.47% portion of equity interest in Drum that had been funded through these notes. Additionally, during the first quarter of 2024, the Company reached agreement to purchase a 0.13% noncontrolling interest in Drum for $0.8 million, the majority which was accrued in March 2024 and ultimately paid in April 2024. The impact of these accrued purchases has been excluded from the Company’s condensed consolidated statement of cash flows for the first quarter of 2024 due to their non-cash nature during the period. The remaining noncontrolling interest in Drum outstanding as of March 31, 2024 was 0.81%.
v3.24.1.u1
Commitments and Contingencies
 3 Months Ended
Mar. 31, 2024
Commitments and Contingencies Disclosure [Abstract]  
Commitments and Contingencies Commitments and Contingencies
Legal Proceedings
The Company is a named party in various legal proceedings arising from the normal course of business. Although the ultimate outcomes of active matters are currently unknown, the Company does not believe any liabilities resulting from these known matters will have a material effect on its financial position, results of operations or cash flows.
The Company maintains liability insurance for various risks associated with its operations. In connection with the liability insurance policies, the Company is responsible for an initial deductible or self-insured retention amount per occurrence, after which the insurance carriers would be responsible for amounts up to the policy limits.
Employment Agreements 
The Company has employment agreements with certain executives and other employees, which provide for compensation and certain other benefits and for severance payments under certain circumstances. Certain employment agreements also contain clauses that become effective upon a change in control of the Company. Upon the occurrence of any of the defined events in the various employment agreements, the Company would be obligated to pay certain amounts to the related employees, which vary with the level of the employees’ respective responsibility.
Concentration of Credit Risk
The Company provides full-service utility services to various customers, primarily utility companies that are located throughout the U.S. and Canada. The Company is subject to concentrations of credit risk related primarily to its revenue and accounts receivable and contract asset positions with customers, which is defined as greater than 10%. No customers accounted for more than 10% of revenue for the first fiscal three months of 2024 or 2023. One Union Electric customer had a combined accounts receivable and contract asset balance of $70.4 million and $84.3 million as of March 31, 2024 and December 31, 2023, respectively, which was approximately 13% and 14% of total accounts receivable and contract assets as of March 31, 2024 and December 31, 2023, respectively.
The Company primarily uses three financial banking institutions. The Company’s cash on deposit with these financial institutions exceeded the federal insurability limits as of March 31, 2024. The Company believes its cash and cash equivalents are managed by high credit quality financial institutions.
Bonds and Parent Guarantees
Many customers, particularly in connection with new construction, require the Company to post performance and payment bonds. These bonds provide a guarantee that the Company will perform under the terms of a contract and pay its subcontractors and vendors. In certain circumstances, the customer may demand that the surety make payments or provide services under the bond, and the Company must reimburse the surety for any expenses or outlays it incurs. The Company may also be required to post letters of credit as collateral in favor of the sureties, which would reduce the borrowing availability under its revolving credit facility. As of March 31, 2024, the Company was not aware of any outstanding material obligations for payments related to these bond obligations.
Performance bonds expire at various times ranging from mechanical completion of a project to a period extending beyond contract completion in certain circumstances, and therefore a determination of maximum potential amounts outstanding requires certain estimates and assumptions. Such amounts can also fluctuate from period to period based upon the mix and level of the Company’s bonded operating activity. As of March 31, 2024, the estimated total amount of outstanding performance and payment bonds was approximately $561.3 million. The Company’s estimated maximum exposure related to the value of the performance bonds outstanding is lowered on each bonded project as the cost to complete is reduced, and each commitment under a performance bond generally extinguishes concurrently with the expiration of its related contractual obligation. The estimated cost to complete these bonded projects was approximately $203.7 million as of March 31, 2024.
Additionally, from time to time, the Company guarantees certain obligations and liabilities of its subsidiaries that may arise in connection with, among other things, contracts with customers, and equipment and real estate lease obligations. These guarantees may cover all of the subsidiary’s unperformed, undischarged and unreleased obligations and liabilities under or in connection with the relevant agreement. The Company is not aware of any claims under any guarantees that are material. The responsibility under a guarantee could exceed the amount recoverable from the subsidiary alone and could materially and adversely affect the Company’s consolidated financial condition, results of operations and cash flows.
v3.24.1.u1
Subsequent Events
 3 Months Ended
Mar. 31, 2024
Subsequent Events [Abstract]  
Subsequent Events Subsequent Events
Centuri IPO
On April 13, 2024, Holdings completed the Separation by issuing 71,664,592 shares of common stock to Southwest Gas Holdings as consideration for the transfer of assets and assumption of liabilities of Centuri. On April 17, 2024, the registration statement related to the Centuri IPO was declared effective, and Holdings’ common stock began trading on the New York Stock Exchange under the ticker “CTRI” on April 18, 2024. For more information about the Separation and Centuri IPO, see “Note 1 — Description of Business.”

Holdings primarily used the net proceeds from the Centuri IPO to pay down $156.0 million of Centuri’s debt under its revolving credit facility and $160.0 million of Centuri’s debt under its term loan facility, and plans to use the remaining proceeds for general corporate and working capital purposes. Centuri’s maximum net leverage ratio covenant under its revolving credit facility was reduced based on the net proceeds received from the Centuri IPO. Centuri continued to be in compliance with all of its covenants through the date of this filing.

Upon completion of the Centuri IPO, the Centuri Omnibus Incentive Plan became effective. Pursuant to this plan, a total of 190,476 restricted stock units with a fair value of approximately $4.0 million were granted to the Chief Executive Officer, and 41,424 restricted stock units with a fair value of approximately $1.0 million were granted to Holdings’ non-employee directors subsequent to the Centuri IPO but prior to the date of this filing. The grant to the Chief Executive Officer vests over three years, and the grants to the non-employee directors vest over a year. The cost of these restricted stock units will be recognized based on the grant-date fair value and number of shares that vest over the service period.

Agreements with Southwest Gas Holdings

In connection with the Separation and the Centuri IPO, Holdings entered into several agreements with Southwest Gas Holdings on April 11, 2024 governing the relationship of the two parties after the Separation and Centuri IPO. These agreements are summarized below and also discussed in more detail within the IPO Prospectus in the section entitled “The Separation Transactions.”

•Separation Agreement: Sets forth the agreements with Southwest Gas Holdings regarding the principal actions to be taken in connection with the Separation and govern, among other matters, (1) the allocation of assets and
liabilities to Holdings and Southwest Gas Holdings (including Holdings’ indemnification obligations, for potentially uncapped amounts, for certain liabilities relating to Holdings’ business activities), (2) certain matters with respect to the Centuri IPO and subsequent disposition transactions by Southwest Gas Holdings, and (3) certain covenants, as described in the IPO Prospectus, regarding Southwest Gas Holdings’ right to designate members to Holdings’ Board, approve certain company actions, and receive information and access rights.
•Tax Matters Agreement: Sets forth responsibilities and obligations with respect to all tax matters, including tax liabilities (including responsibility and potential indemnification obligations for taxes attributable to Holdings’ business and taxes arising, under certain circumstances, in connection with the Separation and a distribution to Southwest Gas Holdings stockholders that is currently intended to be tax-free to Southwest Gas Holdings and its stockholders, if effected), tax attributes, tax contests and tax returns (including Holdings’ continued inclusion in the U.S. federal consolidated group tax return, and certain other combined or similar group tax returns, with Southwest Gas Holdings for applicable tax periods following the Separation, and Holdings’ continuing joint and several liability with Southwest Gas Holdings for such tax returns).
•Registration Rights Agreement: Grants to Southwest Gas Holdings certain registration rights with respect to the shares of Holdings’ common stock owned by Southwest Gas Holdings following the Centuri IPO.
v3.24.1.u1
Pay vs Performance Disclosure - USD ($)
$ in Thousands
 3 Months Ended
Mar. 31, 2024
Apr. 02, 2023
Pay vs Performance Disclosure    
Net loss $ (25,058) $ (8,844)
v3.24.1.u1
Insider Trading Arrangements
 3 Months Ended
Mar. 31, 2024
Trading Arrangements, by Individual  
Rule 10b5-1 Arrangement Adopted false
Non-Rule 10b5-1 Arrangement Adopted false
Rule 10b5-1 Arrangement Terminated false
Non-Rule 10b5-1 Arrangement Terminated false
v3.24.1.u1
Basis of Presentation and Summary of Significant Accounting Policies (Policies)
 3 Months Ended
Mar. 31, 2024
Accounting Policies [Abstract]  
Interim Condensed Consolidated Financial Information
Interim Condensed Consolidated Financial Information
The unaudited condensed consolidated financial statements presented herein are the financial statements of Centuri, the predecessor of Holdings for financial reporting purposes. Holdings had no substantive operations as of March 31, 2024 or December 31, 2023. The unaudited condensed consolidated financial statements and footnotes were prepared in accordance with generally accepted accounting principles in the United States (“GAAP”) for interim financial information and with the instructions to Form 10-Q and Article 10 of Regulation S-X of the U.S. Securities and Exchange Commission (“SEC”). Accordingly, they do not include all of the information and footnotes required by GAAP for complete annual financial statements. Certain information and footnote disclosures, normally included in annual financial statements prepared in accordance with GAAP, have been condensed or omitted pursuant to those rules and regulations. These unaudited condensed consolidated financial statements should be read in conjunction with the Company’s audited consolidated financial statements and the notes thereto for the fiscal year ended December 31, 2023, as included in Holdings’ final IPO prospectus (the “IPO Prospectus”) filed on April 18, 2024 with the SEC pursuant to rule 424(b)(4) under the Securities Act of 1933, as amended relating to Holdings’ Registration Statement on Form S-1. In the opinion of management, all adjustments, consisting only of normal recurring adjustments, necessary to fairly state the financial position, results of operations, comprehensive income and cash flows with respect to the interim condensed consolidated financial statements have been included. The results of operations and comprehensive income for the interim periods are not necessarily indicative of the results for the entire fiscal year. The results of the Company have historically been subject to significant seasonal fluctuations.
Segment Reporting As of and prior to December 31, 2023, the Company reported its results under two reportable segments. In January 2024, the Company appointed a new Chief Executive Officer who acts as the Company’s chief operating decision maker (“CODM”). Following the appointment of the Company’s new Chief Executive Officer, the Company underwent an internal personnel reorganization, causing the Company to re-evaluate its reportable segments based on the information reviewed by the new CODM. See “Note 4 — Segment Information” for additional details.
Fiscal Period
The Company uses a 52/53-week fiscal year that ends on the Sunday closest to the end of the calendar year. Unless otherwise stated, references to months in the Company’s condensed consolidated financial statements relate to fiscal months rather than calendar months. The fiscal three month periods ended March 31, 2024 and April 2, 2023 each had 13 weeks.
Recent Accounting Pronouncements
Recent Accounting Pronouncements
In November 2023, the Financial Accounting Standards Board (“FASB”) issued Accounting Standards Update (“ASU”) 2023-07, “Segment Reporting (Topic 280): Improvements to Reportable Segment Disclosures.” The update improves reportable segment disclosure requirements, primarily through enhanced disclosures about significant segment expenses. This update is effective beginning with the Company’s 2024 fiscal year annual reporting period, with early adoption permitted. The Company is currently evaluating the impact that the adoption of this update will have on its disclosures.

In December 2023, the FASB issued ASU 2023-09, “Income Taxes (Topic 740): Improvements to Income Tax Disclosures.” The update enhances income tax disclosure requirements. This update is effective beginning with the Company’s 2025 fiscal year annual reporting period, with early adoption permitted. The Company is currently evaluating the impact that the adoption of this update will have on its disclosures.

In March 2024, the SEC issued the final rules under SEC Release No. 33-11275, “The Enhancement and Standardization of Climate-Related Disclosures for Investors.” In April 2024, the SEC voluntarily stayed the new rules as a result of pending legal challenges. Absent the stay and the result of pending legal challenges, these rules will require registrants to disclose certain climate-related information, including Scope 1 and Scope 2 greenhouse gas emissions and other climate-related topics, in registration statements and annual reports, when material. Disclosure requirements, absent the results of pending legal challenges, will begin phasing in with the annual reporting for the fiscal year ending 2027 based on Holdings’ current status as a non-accelerated filer. The Company is currently evaluating the impact the rules will have on its disclosures.
v3.24.1.u1
Revenue and Related Balance Sheet Accounts (Tables)
 3 Months Ended
Mar. 31, 2024
Revenue from Contract with Customer [Abstract]  
Schedule of Revenue by Contract
The following table presents the Company’s revenue from contracts with customers disaggregated by contract type (in thousands):
Fiscal Three Months Ended
March 31, 2024April 2, 2023
Contract Type:
Master services agreements$443,242 $547,606 
Bid contracts84,781 105,687 
Total revenue$528,023 $653,293 
Unit-price contracts$307,849 $328,527 
Time and materials contracts109,892 157,851 
Fixed-price contracts110,282 166,915 
Total revenue$528,023 $653,293 
Schedule of Contract Asset and Liability
Contract assets and liabilities consisted of the following (in thousands):
March 31,
2024		December 31,
2023
Current contract assets$257,830 $269,808 
Non-current contract assets16,484 214 
Contract assets, total274,314 270,022 
Contract liabilities(13,648)(43,694)
Net contract assets$260,666 $226,328 
Schedule of Accounts Receivable
Accounts receivable, net consisted of the following (in thousands): 
March 31,
2024		December 31,
2023
Billed on completed contracts and contracts in progress$285,896 $348,021 
Other receivables1,989 1,945 
Accounts receivable, gross287,885 349,966 
Allowance for doubtful accounts(70)(2,512)
Accounts receivable, net$287,815 $347,454 
v3.24.1.u1
Segment Information (Tables)
 3 Months Ended
Mar. 31, 2024
Segment Reporting [Abstract]  
Schedule of Segment Reporting
Revenue and gross profit by segment was as follows (in thousands):
Fiscal Three Months Ended
March 31, 2024April 2, 2023
Revenue:
U.S. Gas$226,578 $259,337 
Canadian Gas34,648 39,303 
Union Electric163,851 205,669 
Non-Union Electric96,615 136,606 
Other6,331 12,378 
Consolidated revenue, net$528,023 $653,293 
Gross profit:
U.S. Gas$(3,976)$3,366 
Canadian Gas5,545 4,476 
Union Electric11,369 15,209 
Non-Union Electric2,800 18,487 
Other(2,459)411 
Consolidated gross profit$13,279 $41,949 
Depreciation expense, included in cost of revenue, by segment was as follows (in thousands):
Fiscal Three Months Ended
March 31, 2024April 2, 2023
U.S. Gas$11,586 $11,678 
Canadian Gas1,506 1,409 
Union Electric6,715 9,449 
Non-Union Electric6,604 7,425 
Other87 75 
Consolidated depreciation expense (1)
$26,498 $30,036 
(1)Depreciation expense within selling, general and administrative expense for each of the fiscal quarters ended March 31, 2024 and April 2, 2023 was $1.2 million and was excluded from the table above as it is not produced or utilized by management to evaluate segment performance.
Capital expenditures by segment were as follows (in thousands):
Fiscal Three Months Ended
March 31, 2024April 2, 2023
U.S. Gas$14,278 $14,906 
Canadian Gas2,990 1,835 
Union Electric4,193 4,538 
Non-Union Electric4,697 530 
Other4,341 1,428 
Consolidated capital expenditures$30,499 $23,237 
v3.24.1.u1
Noncontrolling Interests (Tables)
 3 Months Ended
Mar. 31, 2024
Temporary Equity Disclosure [Abstract]  
Schedule of Redeemable Noncontrolling Interest
The following table depicts changes to the balance of the redeemable noncontrolling interests (in thousands):

Linetec
Services, LLC		Drum Parent
LLC		Redeemable
Noncontrolling
Interests
Balance as of December 31, 2023$91,979 $7,283 $99,262 
Net (loss) income attributable to redeemable noncontrolling interests(193)18 (175)
Redemption value adjustment193 2,256 2,449 
Redeemable noncontrolling interests redeemed(91,979)(5,046)(97,025)
Balance as of March 31, 2024$- $4,511 $4,511 
v3.24.1.u1
Goodwill and Intangible Assets (Tables)
 3 Months Ended
Mar. 31, 2024
Goodwill and Intangible Assets Disclosure [Abstract]  
Schedule of Goodwill
Changes in the carrying amount of goodwill of each of the Company’s reportable segments were as follows (in thousands):

U.S. Gas
Canadian Gas
Union Electric (1)
Non-Union ElectricTotal
Balances as of December 31, 2023$58,160 $93,911 $56,499 $167,322 $375,892 
Effect of exchange rate changes- (2,246)- - (2,246)
Balances as of March 31, 2024$58,160 $91,665 $56,499 $167,322 $373,646 
(1) Net of accumulated impairment of $391.1 million as of March 31, 2024 and December 31, 2023.
v3.24.1.u1
Property and Equipment (Tables)
 3 Months Ended
Mar. 31, 2024
Property, Plant and Equipment [Abstract]  
Schedule of Property and Equipment
Property and equipment consisted of the following (in thousands):
March 31,
2024		December 31,
2023
Property and equipment, gross$1,120,661 $1,118,202 
Accumulated depreciation(582,979)(572,760)
Property and equipment, net$537,682 $545,442 
v3.24.1.u1
Accrued Expenses and Other Current Liabilities (Tables)
 3 Months Ended
Mar. 31, 2024
Payables and Accruals [Abstract]  
Schedule of Accrued Liabilities and Other Current Liabilities
Accrued expenses and other current liabilities consisted of the following (in thousands):
March 31,
2024		December 31,
2023
Accrued redemption of noncontrolling interests$92,801 $— 
Accrued compensation58,927 92,205 
Accrued expenses50,181 55,186 
Accrued insurance23,777 21,794 
Book overdrafts8,141 13,300 
Accrued taxes3,345 3,590 
Accrued interest962 975 
Accrued expenses and other current liabilities$238,134 $187,050 
v3.24.1.u1
Long-Term Debt (Tables)
 3 Months Ended
Mar. 31, 2024
Debt Disclosure [Abstract]  
Schedule of Long-Term Debt
Long-term debt, including outstanding amounts on the Company’s line of credit, consisted of the following (in thousands):
March 31, 2024December 31, 2023
Carrying
Amount
Fair Value (1)
Carrying
Amount
Fair Value (1)
Borrowings under revolving line of credit$125,229 $125,324 $77,121 $77,205 
Term loans under loan facility991,375 991,375 994,238 996,723 
Total loan facility1,116,604 1,116,699 1,071,359 1,073,928 
Equipment loans:
2.30%, due May 2025
4,763 4,655 5,768 5,618 
1.75%, due March 2027
6,654 6,256 7,193 6,740 
1.75%, due March 2027
15,526 14,597 16,783 15,727 
2.96%, due March 2027
15,441 14,760 16,667 15,903 
3.27%, due March 2027
18,587 17,855 20,055 19,237 
3.40%, due March 2027
9,304 8,948 10,037 9,641 
3.51%, due March 2027
18,630 17,952 20,096 19,342 
Total long-term debt1,205,509 $1,201,722 1,167,958 $1,166,136 
Current portion of long-term debt(42,770)(42,552)
Unamortized discount and debt issuance costs(16,192)(17,111)
Long-term debt, net of current portion$1,146,547 $1,108,295 
(1)Fair values as of March 31, 2024 and December 31, 2023 were determined using the Company’s credit rating.
v3.24.1.u1
Leases (Tables)
 3 Months Ended
Mar. 31, 2024
Leases [Abstract]  
Summary of Lease Information
The components of lease expense were as follows (in thousands):
Fiscal Three Months Ended
Lease costClassificationMarch 31, 2024April 2, 2023
Operating lease costCost of revenue and selling, general and administrative expenses$6,631 $4,772 
Finance lease cost:
Amortization of ROU assets
Depreciation (1)
2,112 1,592 
Interest on lease liabilitiesInterest expense, net365 448 
Total finance lease cost2,477 2,040 
Short-term lease cost (2)
Cost of revenue and selling, general and administrative expenses21,260 28,437 
Total lease cost$30,368 $35,249 
(1)Depreciation is included within cost of revenue in the accompanying condensed consolidated statements of operations.
(2)Short-term lease cost includes both leases and rentals with initial terms of 12 months or less.
Supplemental cash flow information related to leases was as follows (in thousands):
Fiscal Three Months Ended
March 31, 2024April 2, 2023
Cash paid for amounts included in the measurement of lease liabilities:
Operating cash flows from operating leases$6,569 $4,509 
Operating cash flows from finance leases365 448 
Financing cash flows from finance leases2,914 3,056 
Right-of-use assets obtained in exchange for lease obligations:
Operating leases$4,904 $17,929 
Finance leases— 1,001 
Supplemental information related to leases was as follows:
March 31,
2024		December 31,
2023
Weighted average remaining lease term (in years):
Operating leases7.197.45
Finance leases3.473.64
Weighted average discount rate:
Operating leases4.96 %4.88 %
Finance leases4.07 %4.02 %
Schedule of Maturities of Finance Lease Liabilities
The following is a schedule of maturities of lease liabilities as of March 31, 2024 (in thousands):
Operating
Leases		Finance
Leases
Fiscal year ended:
Remainder of 2024$19,461 $9,386 
202522,905 10,233 
202620,497 7,646 
202719,061 5,756 
202816,645 1,727 
Thereafter49,076 748 
Total lease payments147,645 35,496 
Less: Amount of lease payments representing interest(23,595)(2,734)
Total$124,050 $32,762 
Schedule of Maturities of Operating Lease Liabilities
The following is a schedule of maturities of lease liabilities as of March 31, 2024 (in thousands):
Operating
Leases		Finance
Leases
Fiscal year ended:
Remainder of 2024$19,461 $9,386 
202522,905 10,233 
202620,497 7,646 
202719,061 5,756 
202816,645 1,727 
Thereafter49,076 748 
Total lease payments147,645 35,496 
Less: Amount of lease payments representing interest(23,595)(2,734)
Total$124,050 $32,762 
v3.24.1.u1
Supplemental Cash Flow Disclosures (Tables)
 3 Months Ended
Mar. 31, 2024
Organization, Consolidation and Presentation of Financial Statements [Abstract]  
Schedule of Supplemental Cash Flow Disclosure
The following table represents the Company’s supplemental cash flow disclosures and non-cash investing activity, excluding lease activity (which is disclosed in “Note 10 — Leases”) (in thousands):
March 31,
2024		April 2,
2023
Non-cash investing activities:
Accrued capital expenditures$3,945 $4,011 
Proceeds from sale of property and equipment in accounts receivable599 441 
v3.24.1.u1
Description of Business (Details) - USD ($)
$ / shares in Units, $ in Millions
Apr. 22, 2024
Apr. 13, 2024
Mar. 31, 2024
Dec. 31, 2023
Subsidiary, Sale of Stock [Line Items]        
Common stock outstanding (in shares)     103.52 103.52
Common stock issued (in shares)     103.52 103.52
Par value (in USD per share)     $ 0.01 $ 0.01
Subsequent Event        
Subsidiary, Sale of Stock [Line Items]        
Par value (in USD per share) $ 0.01      
Proceeds from issuance of private placement $ 54.4      
Underwriting discounts and commissions 18.0      
Sale of stock, net proceed received $ 329.3      
Subsequent Event | Southwest Gas Holdings        
Subsidiary, Sale of Stock [Line Items]        
Sale of stock (in shares)   71,664,592    
IPO | Subsequent Event        
Subsidiary, Sale of Stock [Line Items]        
Sale of stock (in shares) 14,260,000      
Sale of stock (in USD per share) $ 21.00      
Over-Allotment Option | Subsequent Event        
Subsidiary, Sale of Stock [Line Items]        
Sale of stock (in shares) 1,860,000      
Private Placement | Subsequent Event        
Subsidiary, Sale of Stock [Line Items]        
Sale of stock (in shares) 2,591,929      
Southwest Gas Holdings | Centuri Holdings, Inc.        
Subsidiary, Sale of Stock [Line Items]        
Common stock outstanding (in shares)     1,000 1,000
Common stock issued (in shares)     1,000 1,000
Percentage of interest owned     100.00% 100.00%
Southwest Gas Holdings | Centuri Holdings, Inc. | Subsequent Event        
Subsidiary, Sale of Stock [Line Items]        
Common stock outstanding (in shares) 71,665,592      
Percentage of ownership after sale of stock 81.00%      
v3.24.1.u1
Basis of Presentation and Summary of Significant Accounting Policies (Details) - segment
 3 Months Ended 12 Months Ended
Mar. 31, 2024
Dec. 31, 2023
Accounting Policies [Abstract]    
Number of reportable segments 4 2
v3.24.1.u1
Revenue and Related Balance Sheet Accounts - Revenue by Contract (Details) - USD ($)
$ in Thousands
 3 Months Ended
Mar. 31, 2024
Apr. 02, 2023
Disaggregation of Revenue [Line Items]    
Total revenue $ 528,023 $ 653,293
Unit-price contracts    
Disaggregation of Revenue [Line Items]    
Total revenue 307,849 328,527
Time and materials contracts    
Disaggregation of Revenue [Line Items]    
Total revenue 109,892 157,851
Fixed-price contracts    
Disaggregation of Revenue [Line Items]    
Total revenue 110,282 166,915
Master services agreements    
Disaggregation of Revenue [Line Items]    
Total revenue 443,242 547,606
Bid contracts    
Disaggregation of Revenue [Line Items]    
Total revenue $ 84,781 $ 105,687
v3.24.1.u1
Revenue and Related Balance Sheet Accounts - Schedule of Contract Asset and Liability (Details) - USD ($)
$ in Thousands
Mar. 31, 2024
Dec. 31, 2023
Revenue from Contract with Customer [Abstract]    
Current contract assets $ 257,830 $ 269,808
Non-current contract assets 16,484 214
Contract assets, total 274,314 270,022
Contract liabilities (13,648) (43,694)
Net contract assets $ 260,666 $ 226,328
v3.24.1.u1
Revenue and Related Balance Sheet Accounts - Narrative (Details)
$ in Millions
 3 Months Ended
Mar. 31, 2024
USD ($)
contract
Disaggregation of Revenue [Line Items]  
Increase in contract asset $ 4.3
Decrease in contract liability 30.0
Performance obligations $ 276.8
Fixed-price contracts  
Disaggregation of Revenue [Line Items]  
Number of contracts greater than one year | contract 53
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2024-04-01  
Disaggregation of Revenue [Line Items]  
Performance obligation time period 2 years
v3.24.1.u1
Revenue and Related Balance Sheet Accounts - Accounts Receivable (Details) - USD ($)
$ in Thousands
Mar. 31, 2024
Dec. 31, 2023
Revenue from Contract with Customer [Abstract]    
Billed on completed contracts and contracts in progress $ 285,896 $ 348,021
Other receivables 1,989 1,945
Accounts receivable, gross 287,885 349,966
Allowance for doubtful accounts (70) (2,512)
Accounts receivable, net $ 287,815 $ 347,454
v3.24.1.u1
Segment Information - Narrative (Details)
$ in Thousands
 3 Months Ended 12 Months Ended
Mar. 31, 2024
USD ($)
segment
Apr. 02, 2023
USD ($)
Dec. 31, 2023
segment
Segment Reporting Information [Line Items]      
Number of reportable segments | segment 4   2
Total revenue $ 528,023 $ 653,293  
CANADA      
Segment Reporting Information [Line Items]      
Total revenue $ 41,000 $ 51,700  
CANADA | Revenue from Contract with Customer Benchmark | Geographic Concentration Risk      
Segment Reporting Information [Line Items]      
Concentration risk percentage 8.00% 8.00%  
v3.24.1.u1
Segment Information - Revenue and Gross Profit (Details) - USD ($)
$ in Thousands
 3 Months Ended
Mar. 31, 2024
Apr. 02, 2023
Segment Reporting Information [Line Items]    
Consolidated revenue, net $ 528,023 $ 653,293
Consolidated gross profit 13,279 41,949
Operating Segments | U.S. Gas    
Segment Reporting Information [Line Items]    
Consolidated revenue, net 226,578 259,337
Consolidated gross profit (3,976) 3,366
Operating Segments | Canadian Gas    
Segment Reporting Information [Line Items]    
Consolidated revenue, net 34,648 39,303
Consolidated gross profit 5,545 4,476
Operating Segments | Union Electric    
Segment Reporting Information [Line Items]    
Consolidated revenue, net 163,851 205,669
Consolidated gross profit 11,369 15,209
Operating Segments | Non-Union Electric    
Segment Reporting Information [Line Items]    
Consolidated revenue, net 96,615 136,606
Consolidated gross profit 2,800 18,487
Other    
Segment Reporting Information [Line Items]    
Consolidated revenue, net 6,331 12,378
Consolidated gross profit $ (2,459) $ 411
v3.24.1.u1
Segment Information - Depreciation by Segment (Details) - USD ($)
$ in Thousands
 3 Months Ended
Mar. 31, 2024
Apr. 02, 2023
Segment Reporting Information [Line Items]    
Consolidated depreciation expense $ 27,651 $ 31,203
Cost of Sales    
Segment Reporting Information [Line Items]    
Consolidated depreciation expense 26,498 30,036
Selling, General and Administrative Expenses    
Segment Reporting Information [Line Items]    
Consolidated depreciation expense 1,200 1,200
Operating Segments | U.S. Gas | Cost of Sales    
Segment Reporting Information [Line Items]    
Consolidated depreciation expense 11,586 11,678
Operating Segments | Canadian Gas | Cost of Sales    
Segment Reporting Information [Line Items]    
Consolidated depreciation expense 1,506 1,409
Operating Segments | Union Electric | Cost of Sales    
Segment Reporting Information [Line Items]    
Consolidated depreciation expense 6,715 9,449
Operating Segments | Non-Union Electric | Cost of Sales    
Segment Reporting Information [Line Items]    
Consolidated depreciation expense 6,604 7,425
Other | Cost of Sales    
Segment Reporting Information [Line Items]    
Consolidated depreciation expense $ 87 $ 75
v3.24.1.u1
Segment Information - Capital Expenditure by Segment (Details) - USD ($)
$ in Thousands
 3 Months Ended
Mar. 31, 2024
Apr. 02, 2023
Segment Reporting Information [Line Items]    
Consolidated capital expenditures $ 30,499 $ 23,237
Operating Segments | U.S. Gas    
Segment Reporting Information [Line Items]    
Consolidated capital expenditures 14,278 14,906
Operating Segments | Canadian Gas    
Segment Reporting Information [Line Items]    
Consolidated capital expenditures 2,990 1,835
Operating Segments | Union Electric    
Segment Reporting Information [Line Items]    
Consolidated capital expenditures 4,193 4,538
Operating Segments | Non-Union Electric    
Segment Reporting Information [Line Items]    
Consolidated capital expenditures 4,697 530
Other    
Segment Reporting Information [Line Items]    
Consolidated capital expenditures $ 4,341 $ 1,428
v3.24.1.u1
Noncontrolling Interests - Narrative (Details) - USD ($)
$ in Thousands
 1 Months Ended 3 Months Ended
Apr. 30, 2024
Mar. 31, 2024
Mar. 31, 2023
Mar. 31, 2024
Apr. 02, 2023
Dec. 31, 2023
Mar. 31, 2022
Nov. 30, 2021
Nov. 30, 2018
Noncontrolling Interest [Line Items]                  
Redeemable noncontrolling interests redeemed       $ 37 $ 0        
Redemption value adjustment       2,449          
Promissory Notes                  
Noncontrolling Interest [Line Items]                  
Promissory notes, interest           0.02      
Subsequent Event                  
Noncontrolling Interest [Line Items]                  
Redeemable noncontrolling interests redeemed $ 800                
Drum Parent LLC                  
Noncontrolling Interest [Line Items]                  
Redemption value adjustment       2,256          
Drum Parent LLC | Subsequent Event                  
Noncontrolling Interest [Line Items]                  
Redeemable noncontrolling interests redeemed 800                
Linetec Services, LLC                  
Noncontrolling Interest [Line Items]                  
Redemption value adjustment       $ 193          
Linetec Services, LLC | Subsequent Event                  
Noncontrolling Interest [Line Items]                  
Redeemable noncontrolling interests redeemed $ 92,000                
Linetec Services, LLC                  
Noncontrolling Interest [Line Items]                  
Additional noncontrolling interest ownership percentage redeemed during the period     5.00%            
Linetec Services, LLC | Previous Lintec Owner                  
Noncontrolling Interest [Line Items]                  
Percentage owned by noncontrolling owner   10.00% 10.00% 10.00%     15.00%   20.00%
Drum Parent LLC                  
Noncontrolling Interest [Line Items]                  
Additional noncontrolling interest ownership percentage redeemed during the period   0.13%   0.13%          
Percentage of NCI redeemed   0.0047   0.0047          
Drum Parent LLC | Members Of Management Of Riggs Distler & Company, Inc.                  
Noncontrolling Interest [Line Items]                  
Percentage owned by noncontrolling owner           1.41%   1.42%  
Drum Parent LLC | Employees Of Riggs Distler & Company, Inc.                  
Noncontrolling Interest [Line Items]                  
Percentage owned by noncontrolling owner   0.81%   0.81%          
v3.24.1.u1
Noncontrolling Interests - Schedule of Redeemable NCI (Details) - USD ($)
$ in Thousands
 3 Months Ended
Mar. 31, 2024
Apr. 02, 2023
Increase (Decrease) in Temporary Equity [Roll Forward]    
Balance as of December 31, 2023 $ 99,262  
Net (loss) income attributable to redeemable noncontrolling interests (175) $ 1,739
Redemption value adjustment 2,449  
Redeemable noncontrolling interests redeemed (97,025)  
Balance as of March 31, 2024 4,511  
Linetec Services, LLC    
Increase (Decrease) in Temporary Equity [Roll Forward]    
Balance as of December 31, 2023 91,979  
Net (loss) income attributable to redeemable noncontrolling interests (193)  
Redemption value adjustment 193  
Redeemable noncontrolling interests redeemed (91,979)  
Balance as of March 31, 2024 0  
Drum Parent LLC    
Increase (Decrease) in Temporary Equity [Roll Forward]    
Balance as of December 31, 2023 7,283  
Net (loss) income attributable to redeemable noncontrolling interests 18  
Redemption value adjustment 2,256  
Redeemable noncontrolling interests redeemed (5,046)  
Balance as of March 31, 2024 $ 4,511  
v3.24.1.u1
Goodwill and Intangible Assets - Goodwill Rollforward (Details) - USD ($)
$ in Thousands
 3 Months Ended
Mar. 31, 2024
Dec. 31, 2023
Goodwill [Roll Forward]    
Balances as of December 31, 2023 $ 375,892  
Effect of exchange rate changes (2,246)  
Balances as of March 31, 2024 373,646  
U.S. Gas    
Goodwill [Roll Forward]    
Balances as of December 31, 2023 58,160  
Effect of exchange rate changes 0  
Balances as of March 31, 2024 58,160  
Canadian Gas    
Goodwill [Roll Forward]    
Balances as of December 31, 2023 93,911  
Effect of exchange rate changes (2,246)  
Balances as of March 31, 2024 91,665  
Union Electric    
Goodwill [Roll Forward]    
Balances as of December 31, 2023 56,499  
Effect of exchange rate changes 0  
Balances as of March 31, 2024 56,499  
Accumulated impairment 391,100 $ 391,100
Non-Union Electric    
Goodwill [Roll Forward]    
Balances as of December 31, 2023 167,322  
Effect of exchange rate changes 0  
Balances as of March 31, 2024 $ 167,322  
v3.24.1.u1
Goodwill and Intangible Assets - Narrative (Details) - USD ($)
$ in Thousands
 3 Months Ended
Mar. 31, 2024
Apr. 02, 2023
Dec. 31, 2023
Goodwill [Line Items]      
Goodwill, net $ 373,646   $ 375,892
Amortization of finite-lived assets 6,668 $ 6,667  
Reporting Unit, Not Meeting Quantitative Thresholds For Separate Reporting      
Goodwill [Line Items]      
Goodwill gross 10,800   10,800
Accumulated impairment 10,800   10,800
Goodwill, net $ 0   $ 0
v3.24.1.u1
Property and Equipment - Schedule of Property and Equipment (Details) - USD ($)
$ in Thousands
Mar. 31, 2024
Dec. 31, 2023
Property, Plant and Equipment [Abstract]    
Property and equipment, gross $ 1,120,661 $ 1,118,202
Accumulated depreciation (582,979) (572,760)
Property and equipment, net $ 537,682 $ 545,442
v3.24.1.u1
Property and Equipment - Narrative (Details) - USD ($)
$ in Thousands
 3 Months Ended
Mar. 31, 2024
Apr. 02, 2023
Property, Plant and Equipment [Abstract]    
Depreciation $ 27,651 $ 31,203
Gain on sale of equipment $ 944 $ 661
v3.24.1.u1
Accrued Expenses and Other Current Liabilities (Details) - USD ($)
$ in Thousands
Mar. 31, 2024
Dec. 31, 2023
Payables and Accruals [Abstract]    
Accrued redemption of noncontrolling interests $ 92,801 $ 0
Accrued compensation 58,927 92,205
Accrued expenses 50,181 55,186
Accrued insurance 23,777 21,794
Book overdrafts 8,141 13,300
Accrued taxes 3,345 3,590
Accrued interest 962 975
Accrued expenses and other current liabilities $ 238,134 $ 187,050
v3.24.1.u1
Long-Term Debt - Components of Debt (Details) - USD ($)
$ in Thousands
Mar. 31, 2024
Dec. 31, 2023
Debt Instrument [Line Items]    
Total long-term debt $ 1,205,509 $ 1,167,958
Fair value 1,201,722 1,166,136
Current portion of long-term debt (42,770) (42,552)
Unamortized discount and debt issuance costs (16,192) (17,111)
Long-term debt, net of current portion 1,146,547 1,108,295
Equipment loans | 2.30%, due May 2025    
Debt Instrument [Line Items]    
Total long-term debt 4,763 5,768
Fair value $ 4,655 5,618
Debt instrument, stated percentage 2.30%  
Equipment loans | 1.75%, due March 2027    
Debt Instrument [Line Items]    
Total long-term debt $ 6,654 7,193
Fair value $ 6,256 6,740
Debt instrument, stated percentage 1.75%  
Equipment loans | 1.75%, due March 2027    
Debt Instrument [Line Items]    
Total long-term debt $ 15,526 16,783
Fair value $ 14,597 15,727
Debt instrument, stated percentage 1.75%  
Equipment loans | 2.96%, due March 2027    
Debt Instrument [Line Items]    
Total long-term debt $ 15,441 16,667
Fair value $ 14,760 15,903
Debt instrument, stated percentage 2.96%  
Equipment loans | 3.27%, due March 2027    
Debt Instrument [Line Items]    
Total long-term debt $ 18,587 20,055
Fair value $ 17,855 19,237
Debt instrument, stated percentage 3.27%  
Equipment loans | 3.40%, due March 2027    
Debt Instrument [Line Items]    
Total long-term debt $ 9,304 10,037
Fair value $ 8,948 9,641
Debt instrument, stated percentage 3.40%  
Equipment loans | 3.51%, due March 2027    
Debt Instrument [Line Items]    
Total long-term debt $ 18,630 20,096
Fair value $ 17,952 19,342
Debt instrument, stated percentage 3.51%  
Line of Credit | Secured Term Loan And Revolving Credit Facility    
Debt Instrument [Line Items]    
Total long-term debt $ 1,116,604 1,071,359
Fair value 1,116,699 1,073,928
Line of Credit | Secured Revolving Credit Facility | Revolving Credit Facility    
Debt Instrument [Line Items]    
Total long-term debt 125,229 77,121
Fair value 125,324 77,205
Line of Credit | Secured Term Loan Facility | Secured Debt    
Debt Instrument [Line Items]    
Total long-term debt 991,375 994,238
Fair value $ 991,375 $ 996,723
v3.24.1.u1
Long-Term Debt - Narrative (Details)
$ in Thousands
 3 Months Ended 12 Months Ended
May 31, 2023
Nov. 04, 2022
USD ($)
Mar. 31, 2024
USD ($)
loan
Apr. 02, 2023
USD ($)
Dec. 31, 2025
Dec. 30, 2024
Dec. 31, 2022
Dec. 29, 2024
Sep. 29, 2024
Jun. 30, 2024
Dec. 31, 2023
USD ($)
Nov. 03, 2022
USD ($)
Aug. 27, 2021
USD ($)
Aug. 26, 2021
USD ($)
Debt Instrument [Line Items]                            
Assets securing the facility     $ 2,119,306               $ 2,189,908      
Amortization related to debt issuance costs     1,318 $ 1,260                    
Fair value     $ 1,201,722               1,166,136      
Equipment loans                            
Debt Instrument [Line Items]                            
Number of equipment loans | loan     7                      
Debt instrument, face amount     $ 170,000                      
Prepayment penalty term             3 years              
Secured Term Loan And Revolving Credit Facility | Line of Credit                            
Debt Instrument [Line Items]                            
Fair value     $ 1,116,699               $ 1,073,928      
Secured Debt | Secured Term Loan Facility | Line of Credit                            
Debt Instrument [Line Items]                            
Maximum borrowing                         $ 1,145,000 $ 590,000
Discount rate                         1.00%  
Weighted average interest rate     7.94%               7.97%      
Debt issuance costs     $ 16,200               $ 17,100      
Fair value     991,375               996,723      
Secured Debt | Secured Term Loan Facility | Line of Credit | Asset Pledged as Collateral                            
Debt Instrument [Line Items]                            
Assets securing the facility     $ 2,000,000                      
Secured Debt | Secured Term Loan Facility | Line of Credit | Base Rate                            
Debt Instrument [Line Items]                            
Applicable margins 1.50%                          
Secured Debt | Secured Term Loan Facility | Line of Credit | Secured Overnight Financing Rate (SOFR)                            
Debt Instrument [Line Items]                            
Applicable margins 2.50%                          
Revolving Credit Facility | Secured Revolving Credit Facility | Line of Credit                            
Debt Instrument [Line Items]                            
Maximum borrowing                         $ 400,000  
Dividend restriction     50.00%                      
Leverage ratio     5.75                      
Unused letters of credit     $ 201,500                      
Debt issuance costs     4,300               4,200      
Fair value     125,324               77,205      
Revolving Credit Facility | Secured Revolving Credit Facility | Line of Credit | Forecast                            
Debt Instrument [Line Items]                            
Leverage ratio           4.00   5.00 5.75 6.00        
Interest coverage ratio         2.50 2.00                
Revolving Credit Facility | Secured Revolving Credit Facility | Line of Credit | Minimum                            
Debt Instrument [Line Items]                            
Weighted average interest rate   8.01%                        
Commitment fee percentages   0.15%                        
Revolving Credit Facility | Secured Revolving Credit Facility | Line of Credit | Maximum                            
Debt Instrument [Line Items]                            
Weighted average interest rate   7.66%                        
Commitment fee percentages   0.35%                        
Revolving Credit Facility | Secured Revolving Credit Facility | Line of Credit | Base Rate | Minimum                            
Debt Instrument [Line Items]                            
Applicable margins   0.00%                        
Revolving Credit Facility | Secured Revolving Credit Facility | Line of Credit | Base Rate | Maximum                            
Debt Instrument [Line Items]                            
Applicable margins   1.50%                        
Revolving Credit Facility | Secured Revolving Credit Facility | Line of Credit | Secured Overnight Financing Rate (SOFR) | Minimum                            
Debt Instrument [Line Items]                            
Applicable margins   1.00%                        
Revolving Credit Facility | Secured Revolving Credit Facility | Line of Credit | Secured Overnight Financing Rate (SOFR) | Maximum                            
Debt Instrument [Line Items]                            
Applicable margins   2.50%                        
Letter of Credit | Secured Term Loan And Revolving Credit Facility                            
Debt Instrument [Line Items]                            
Maximum borrowing   $ 125,000                   $ 100,000    
Unused letters of credit     $ 51,700               $ 48,600      
v3.24.1.u1
Leases - Narrative (Details)
 3 Months Ended
Mar. 31, 2024
Lessee, Lease, Description [Line Items]  
Termination period 1 year
Maximum  
Lessee, Lease, Description [Line Items]  
Remaining lease term 15 years
Renewal term 5 years
v3.24.1.u1
Leases - Schedule of Lease Expense (Details) - USD ($)
$ in Thousands
 3 Months Ended
Mar. 31, 2024
Apr. 02, 2023
Leases [Abstract]    
Operating lease cost $ 6,631 $ 4,772
Finance lease cost:    
Amortization of ROU assets 2,112 1,592
Interest on lease liabilities 365 448
Total finance lease cost 2,477 2,040
Short-term lease cost 21,260 28,437
Total lease cost $ 30,368 $ 35,249
v3.24.1.u1
Leases - Schedule of Supplemental Cash Flow Information (Details) - USD ($)
$ in Thousands
 3 Months Ended
Mar. 31, 2024
Apr. 02, 2023
Cash paid for amounts included in the measurement of lease liabilities:    
Operating cash flows from operating leases $ 6,569 $ 4,509
Operating cash flows from finance leases 365 448
Financing cash flows from finance leases 2,914 3,056
Right-of-use assets obtained in exchange for lease obligations:    
Operating leases 4,904 17,929
Finance leases $ 0 $ 1,001
v3.24.1.u1
Leases - Supplemental Information Related to Leases (Details)
Mar. 31, 2024
Dec. 31, 2023
Weighted average remaining lease term (in years):    
Operating leases 7 years 2 months 8 days 7 years 5 months 12 days
Finance leases 3 years 5 months 19 days 3 years 7 months 20 days
Weighted average discount rate:    
Operating leases 4.96% 4.88%
Finance leases 4.07% 4.02%
v3.24.1.u1
Leases - Schedule of Lease Maturities (Details)
$ in Thousands
Mar. 31, 2024
USD ($)
Operating Leases  
Remainder of 2024 $ 19,461
2025 22,905
2026 20,497
2027 19,061
2028 16,645
Thereafter 49,076
Total lease payments 147,645
Less: Amount of lease payments representing interest (23,595)
Total 124,050
Finance Leases  
Remainder of 2024 9,386
2025 10,233
2026 7,646
2027 5,756
2028 1,727
Thereafter 748
Total lease payments 35,496
Less: Amount of lease payments representing interest (2,734)
Total $ 32,762
v3.24.1.u1
Income Taxes (Details) - USD ($)
$ in Millions
 3 Months Ended
Mar. 31, 2024
Apr. 02, 2023
Dec. 31, 2023
Income Tax Disclosure [Abstract]      
Effective tax rate 45.20% 37.20%  
Unrecognized tax benefits $ 0.5   $ 0.5
v3.24.1.u1
Supplemental Cash Flow Disclosures - Non-Cash Investing Activity (Details) - USD ($)
$ in Thousands
 3 Months Ended
Mar. 31, 2024
Apr. 02, 2023
Non-cash investing activities:    
Accrued capital expenditures $ 3,945 $ 4,011
Proceeds from sale of property and equipment in accounts receivable $ 599 $ 441
v3.24.1.u1
Supplemental Cash Flow Disclosures - Narrative (Details) - USD ($)
$ in Thousands
Mar. 31, 2024
Dec. 31, 2023
Organization, Consolidation and Presentation of Financial Statements [Abstract]    
Accrued redemption of noncontrolling interests $ 92,801 $ 0
v3.24.1.u1
Related Parties (Details) - USD ($)
 1 Months Ended 3 Months Ended
Apr. 30, 2024
Mar. 31, 2024
Mar. 31, 2024
Apr. 02, 2023
Dec. 31, 2023
Nov. 30, 2021
Related Party Transaction [Line Items]            
Revenues from Southwest Gas     $ 528,023,000 $ 653,293,000    
Gross profit     13,279,000 41,949,000    
Accounts receivable, net   $ 287,815,000 287,815,000   $ 347,454,000  
Contract assets   257,830,000 257,830,000   269,808,000  
Contract liabilities   13,648,000 13,648,000   43,694,000  
Selling, general and administrative expenses     28,550,000 23,539,000    
Accrued taxes   $ 3,345,000 3,345,000   $ 3,590,000  
Redeemable noncontrolling interests redeemed     $ 37,000 0    
Promissory Notes            
Related Party Transaction [Line Items]            
Promissory notes, interest         0.02  
Subsequent Event            
Related Party Transaction [Line Items]            
Redeemable noncontrolling interests redeemed $ 800,000          
Drum Parent LLC            
Related Party Transaction [Line Items]            
Additional noncontrolling interest ownership percentage redeemed during the period   0.13% 0.13%      
Percentage of NCI redeemed   0.0047 0.0047      
Members Of Management Of Riggs Distler & Company, Inc. | Drum Parent LLC            
Related Party Transaction [Line Items]            
Percentage owned by noncontrolling owner         1.41% 1.42%
Employees Of Riggs Distler & Company, Inc. | Drum Parent LLC            
Related Party Transaction [Line Items]            
Percentage owned by noncontrolling owner   0.81% 0.81%      
Related Party            
Related Party Transaction [Line Items]            
Revenues from Southwest Gas     $ 23,278,000 28,804,000    
Gross profit     1,400,000 1,600,000    
Accounts receivable, net   $ 8,409,000 8,409,000 12,300,000 $ 12,258,000  
Contract assets   3,461,000 3,461,000 3,200,000 3,208,000  
Contract liabilities   0 0   0  
Selling, general and administrative expenses     400,000 $ 300,000    
Accrued taxes   0 0   0  
Income taxes receivable   $ 0 $ 0   $ 0  
Revenue from Contract with Customer Benchmark | Customer Concentration Risk | Related Party | Southwest Gas Corporation            
Related Party Transaction [Line Items]            
Concentration risk percentage     4.00% 4.00%    
Gross Profit Benchmark | Customer Concentration Risk | Related Party | Southwest Gas Corporation            
Related Party Transaction [Line Items]            
Concentration risk percentage     11.00% 4.00%    
Accounts Receivable | Customer Concentration Risk | Related Party | Southwest Gas Corporation            
Related Party Transaction [Line Items]            
Concentration risk percentage     3.00% 4.00%    
v3.24.1.u1
Commitments and Contingencies (Details)
$ in Millions
 3 Months Ended 12 Months Ended
Mar. 31, 2024
USD ($)
banking_institution
Dec. 31, 2023
USD ($)
Other Commitments [Line Items]    
Number of financial banking institutions | banking_institution 3  
Performance And Payment Bond    
Other Commitments [Line Items]    
Outstanding performance and payment bonds $ 561.3  
Cost to complete bonded projects 203.7  
Customer Concentration Risk | Union Electric    
Other Commitments [Line Items]    
Combined accounts receivable and contract assets $ 70.4 $ 84.3
Accounts Receivable and Contract Assets Benchmark | Customer Concentration Risk | Union Electric    
Other Commitments [Line Items]    
Concentration risk percentage 13.00% 14.00%
v3.24.1.u1
Subsequent Events (Details) - USD ($)
$ in Thousands
 3 Months Ended
Apr. 18, 2024
Apr. 17, 2024
Apr. 13, 2024
Mar. 31, 2024
Apr. 02, 2023
Subsequent Event [Line Items]          
Pay down of debt       $ 5,931 $ 71,017
Subsequent Event | Restricted Stock Units | Chief Executive Officer          
Subsequent Event [Line Items]          
Restricted stock units granted (in shares) 190,476        
Restricted stock units value $ 4,000        
Vesting period 3 years        
Subsequent Event | Restricted Stock Units | Holdings' Non-Employee Directors          
Subsequent Event [Line Items]          
Restricted stock units granted (in shares) 41,424        
Restricted stock units value $ 1,000        
Subsequent Event | Southwest Gas Holdings          
Subsequent Event [Line Items]          
Sale of stock (in shares)     71,664,592    
Subsequent Event | Line of Credit | Secured Revolving Credit Facility | Revolving Credit Facility          
Subsequent Event [Line Items]          
Pay down of debt   $ 156,000      
Subsequent Event | Line of Credit | Secured Term Loan Facility | Secured Debt          
Subsequent Event [Line Items]          
Pay down of debt   $ 160,000