Business and Organization	6 Months Ended
Jun. 30, 2025
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Business and Organization	1. Business and Organization Comfort Systems USA, Inc., a Delaware corporation, provides comprehensive mechanical and electrical contracting services, which principally includes heating, ventilation and air conditioning (“HVAC”), plumbing, electrical, piping and controls, as well as off-site construction, monitoring and fire protection. We build, install, maintain, repair and replace mechanical, electrical and plumbing (“MEP”) systems throughout the United States. The terms “Comfort Systems,” “we,” “us,” or the “Company,” refer to Comfort Systems USA, Inc. or Comfort Systems USA, Inc. and its consolidated subsidiaries, as appropriate in the context.

The entire disclosure for the nature of an entity's business, major products or services, principal markets including location, and the relative importance of its operations in each business and the basis for the determination, including but not limited to, assets, revenues, or earnings. For an entity that has not commenced principal operations, disclosures about the risks and uncertainties related to the activities in which the entity is currently engaged and an understanding of what those activities are being directed toward.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name Accounting Standards Codification
-Topic 275
-Publisher FASB
-URI https://asc.fasb.org/275/tableOfContent

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (a)
-SubTopic 10
-Topic 275
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482861/275-10-50-1

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