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Income Taxes - Narrative (Details) - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2025 | Dec. 31, 2024 | Dec. 31, 2023
Income Tax Contingency [Line Items] |  |  |
Loss before income tax | $ 55,142 | $ 23,122 | $ 53,944
Valuation allowance | 181,533 | 129 | 0
Decreases based on tax positions related to prior periods | 2,453 | 0 | $ 0
Decrease in unrecognized tax benefits | 2,200 |  |
Income tax penalties and interest accrued | 3,100 | 4,300 |
Variable Interest Entity, Primary Beneficiary |  |  |
Income Tax Contingency [Line Items] |  |  |
Increase in unrecognized tax benefits |  | (7,700) |
Income tax penalties and interest accrued | 2,700 | $ 4,100 |
Investment In Legence Holdings |  |  |
Income Tax Contingency [Line Items] |  |  |
Valuation allowance | 169,200 |  |
Domestic Tax Jurisdiction |  |  |
Income Tax Contingency [Line Items] |  |  |
Interest carryforward | 23,300 |  |
Operating loss carryforwards | 34,200 |  |
State and Local Jurisdiction |  |  |
Income Tax Contingency [Line Items] |  |  |
Operating loss carryforwards | 62,000 |  |
Net operating losses | $ 2,400 |  |

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