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Investments - Additional Information (Detail) - USD ($) $ in Millions | 12 Months Ended |
--- | --- | ---
Dec. 31, 2023 | Dec. 31, 2022 | Dec. 31, 2021
Schedule of Equity Method Investments [Line Items] |  |  |
Total assets | $ 51,615.8 | $ 38,358.4 | $ 33,236.1
Total liabilities of variable interest entities | $ 40,800.5 | 29,168.2 |
Ownership interest held | 50.00% |  |
Variable Interest Entity, Not Primary Beneficiary [Member] |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |
Ownership interest held | 12.00% |  |
Chem-Mod Clean-Coal Venture [Member] | VIE [Member] |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |
Total assets | $ 0.5 | 14.8 |
Total liabilities of variable interest entities | 0.5 | 1.1 |
Chem-Mod Clean-Coal Venture - U.S. and Canadian Operations [Member] |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |
Total revenues of limited liability companies | 0.4 | 1.0 |
Total expenses of limited liability companies | $ 25.8 | $ 5.7 |
Chem-Mod International LLC [Member] |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |
Ownership interest held | 31.50% |  |
Chem Mod L L C [Member] |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |
Ownership interest held | 46.50% |  |

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