Condensed Consolidated Statements of Comprehensive Income (Loss) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2026	Mar. 31, 2025
Statement of Comprehensive Income [Abstract]
Net income (loss)	$ 17,394	$ (19,139)
Other comprehensive income (loss), net:
Gain (loss) related to interest rate swaps, net of tax	3,110	(6,214)
Other comprehensive income (loss)	3,110	(6,214)
Comprehensive income (loss)	20,504	(25,353)
Comprehensive income attributable to noncontrolling interests	2,472	2,074
Comprehensive income (loss) attributable to Legence	$ 18,032	$ (27,427)

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income (loss) and other comprehensive income (loss), attributable to noncontrolling interests. Excludes changes in equity resulting from investments by owners and distributions to owners.

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Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income. Excludes changes in equity resulting from investments by owners and distributions to owners.

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Amount after tax and reclassification adjustments of other comprehensive income (loss).

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The consolidated profit or loss for the period, net of income taxes, including the portion attributable to the noncontrolling interest.

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