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Income Taxes - Roll-forward of Unrecognized Tax Benefits and Associated Accrued Interest and Penalties (Detail) - USD ($) | 12 Months Ended
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Dec. 31, 2025 | Dec. 31, 2024 | Dec. 31, 2023
Income Tax Contingency [Line Items] |  |  |
Opening balance at January 1 | $ 0 | $ 14,800,000 | $ 13,400,000
Reductions for tax positions of prior periods | 0 | (15,600,000) | 0
Additions for tax positions of prior periods | 0 | 800,000 | 1,400,000
Closing balance at December 31 | 0 | 0 | 14,800,000
Current | 0 | 0 | (1,200,000)
Non-current | 0 | 0 | 13,600,000
Unrecognized Tax Benefits [Member] |  |  |
Income Tax Contingency [Line Items] |  |  |
Opening balance at January 1 | 0 | 10,500,000 | 10,200,000
Reductions for tax positions of prior periods | 0 | (10,500,000) | 0
Additions for tax positions of prior periods | 0 | 0 | 300,000
Closing balance at December 31 | 0 | 0 | 10,500,000
Current | 0 | 0 | (1,000,000)
Non-current | 0 | 0 | 9,500,000
Interest and Penalties [Member] |  |  |
Income Tax Contingency [Line Items] |  |  |
Opening balance at January 1 | 0 | 4,300,000 | 3,200,000
Reductions for tax positions of prior periods |  | (5,100,000) | 0
Additions for tax positions of prior periods |  | 800,000 | 1,100,000
Closing balance at December 31 | 0 | 0 | 4,300,000
Current | 0 | 0 | (200,000)
Non-current | $ 0 | $ 0 | $ 4,100,000

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