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Long-Term Debt - Summary of Debt Refinancing Costs (Detail) - USD ($) $ in Millions | 12 Months Ended
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Dec. 31, 2025 | Dec. 31, 2024 | Dec. 31, 2023
Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Abstract] |  |  |
Gross cost at January 1 | $ 1.7 | $ 1.4 |
Capitalized in the year | 0.0 | 0.3 |
Gross cost | 1.7 | 1.7 | $ 1.4
Accumulated amortization,Beginning Balance | (0.6) | (0.2) |
Amortization in the year | (0.4) | (0.4) | (0.4)
Accumulated amortization,Ending balance | (1.0) | (0.6) | $ (0.2)
Deferred finance costs, net | $ 0.7 | $ 1.1 |

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