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Consolidated Variable Interest Entity - Fortis - Additional Information (Detail) - USD ($) $ in Millions | 1 Months Ended | 3 Months Ended |
--- | --- | --- | ---
May 31, 2023 | Mar. 31, 2024 | Mar. 31, 2025
Third Party Shareholders [Member] | Nonredeemable NCI [Member] |  |  |
Business Acquisition [Line Items] |  |  |
Ownership percentage | 100.00% |  | 100.00%
Other Investors [Member] | Nonredeemable NCI [Member] |  |  |
Business Acquisition [Line Items] |  |  |
Ownership percentage | 98.00% |  | 98.00%
Series A Preferred Shares [Member] | Nonredeemable NCI [Member] |  |  |
Business Acquisition [Line Items] |  |  |
Ownership percentage | 2.00% |  | 2.00%
Fortis Therapeutics [Member] |  |  |
Business Acquisition [Line Items] |  |  |
Payment to options exercised | $ 80.0 |  |
Contingent payment associated with business acquisition | 200.0 |  |
Product development obligations | $ 5.4 | $ 1.7 |

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