Business and Organization, Basis of Presentation and Accounting Policies	6 Months Ended
Jun. 30, 2026
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Business and Organization, Basis of Presentation and Accounting Policies	1. BUSINESS AND ORGANIZATION, BASIS OF PRESENTATION AND ACCOUNTING POLICIES: Nature of Operations Quanta Services, Inc. (together with its subsidiaries, Quanta) is a leading provider of comprehensive infrastructure solutions for the electric and gas utility, power generation, large load center, manufacturing, communications, pipeline and energy industries in the United States, Canada, Australia and select other international markets. Quanta provides design, engineering, procurement, construction, upgrade and repair and maintenance services for infrastructure within each of these industries, including electric power transmission and distribution networks; substation facilities; wind, solar and gas power generation and transmission and battery storage facilities; low voltage electrical, mechanical, plumbing and process infrastructure for large load centers, such as data center, advanced manufacturing and industrial facilities; communications and cable multi-system operator networks; gas utility systems; pipeline transmission systems and facilities; and downstream industrial facilities. Basis of Presentation and Principles of Consolidation These unaudited condensed consolidated financial statements have been prepared in accordance with the instructions to Form 10-Q and Rule 10-01 of Regulation S-X for interim financial information. Certain information and footnote disclosures, normally included in annual financial statements prepared in accordance with generally accepted accounting principles in the United States (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 audited consolidated financial statements and notes thereto of Quanta’s Annual Report on Form 10-K for the year ended December 31, 2025. Quanta believes that the disclosures made are adequate to make the information presented not misleading. 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. Recently Issued Accounting Standards There have been no developments to recently issued accounting standards, including the expected dates of adoption and estimated effects on Quanta’s consolidated financial statements and footnote disclosures, from those disclosed in Quanta’s Annual Report on Form 10-K for the year ended December 31, 2025. Seasonality The results of Quanta have historically been subject to seasonal fluctuations. The results of operations, comprehensive income and operating cash flows for the interim periods are not necessarily indicative of the results for the entire fiscal year.

Business and Organization, Basis of Presentation and Accounting Policies

6 Months Ended

Jun. 30, 2026

Organization, Consolidation and Presentation of Financial Statements [Abstract]

Business and Organization, Basis of Presentation and Accounting Policies

1. BUSINESS AND ORGANIZATION, BASIS OF PRESENTATION AND ACCOUNTING POLICIES:

Nature of Operations

Quanta Services, Inc. (together with its subsidiaries, Quanta) is a leading provider of comprehensive infrastructure solutions for the electric and gas utility, power generation, large load center, manufacturing, communications, pipeline and energy industries in the United States, Canada, Australia and select other international markets. Quanta provides design, engineering, procurement, construction, upgrade and repair and maintenance services for infrastructure within each of these industries, including electric power transmission and distribution networks; substation facilities; wind, solar and gas power generation and transmission and battery storage facilities; low voltage electrical, mechanical, plumbing and process infrastructure for large load centers, such as data center, advanced manufacturing and industrial facilities; communications and cable multi-system operator networks; gas utility systems; pipeline transmission systems and facilities; and downstream industrial facilities.

Basis of Presentation and Principles of Consolidation

These unaudited condensed consolidated financial statements have been prepared in accordance with the instructions to Form 10-Q and Rule 10-01 of Regulation S-X for interim financial information. Certain information and footnote disclosures, normally included in annual financial statements prepared in accordance with generally accepted accounting principles in the United States (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 audited consolidated financial statements and notes thereto of Quanta’s Annual Report on Form 10-K for the year ended December 31, 2025. Quanta believes that the disclosures made are adequate to make the information presented not misleading. 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.

Recently Issued Accounting Standards

There have been no developments to recently issued accounting standards, including the expected dates of adoption and estimated effects on Quanta’s consolidated financial statements and footnote disclosures, from those disclosed in Quanta’s Annual Report on Form 10-K for the year ended December 31, 2025.

Seasonality

The results of Quanta have historically been subject to seasonal fluctuations. The results of operations, comprehensive income and operating cash flows for the interim periods are not necessarily indicative of the results for the entire fiscal year.