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v3.26.1

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 |  |

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