Limited Partners Capital, Unit Conversion Ratio

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- Definition

Stock Issued During Period, Shares, Effect Of Reorganization

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- Definition

Tax Receivable Agreement, Cash Tax Savings Owed

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- Definition

Tax Receivable Agreement, Cash Tax Savings Retained

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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- Definition

Cash received on stock transaction after deduction of issuance costs.

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- Definition

The number of shares issued or sold by the subsidiary or equity method investee per stock transaction.

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- Definition

Per share amount received by subsidiary or equity investee for each share of common stock issued or sold in the stock transaction.

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Nature of Operations (Details) $ / shares in Units, $ in Millions			12 Months Ended
	Dec. 16, 2025 $ / shares shares	Sep. 15, 2025 USD ($) $ / shares shares	Dec. 31, 2025 shares
Product Information [Line Items]
Conversion ratio			1
Cash tax savings (as a percent)		0.85
Cash tax savings retained (as a percent)		15.00%
Common Class A
Product Information [Line Items]
Conversion ratio			1
Common Class A \| Legence Parent II LLC
Product Information [Line Items]
Effect of reorganization (in shares)			28,844,369
Common Class A \| Legence Parent \| Legence Intermediate
Product Information [Line Items]
Effect of reorganization (in shares)			178,571
Common Class A \| Common Stock
Product Information [Line Items]
Effect of reorganization (in shares)			29,022,940
IPO
Product Information [Line Items]
Number of shares issued (in shares)		29,487,627
Sale of stock, price (in usd per share) \| $ / shares		$ 28.00
Consideration received on transaction \| $		$ 780.2
Secondary Offering \| Common Class A
Product Information [Line Items]
Number of shares issued (in shares)	8,402,178
Sale of stock, price (in usd per share) \| $ / shares	$ 45.00