Business Combination and Divestitures - Schedule of Receipts (Details) - Mallinckrodt & Endo Merger $ in Millions	Jul. 31, 2025 USD ($)
Business Acquisition [Line Items]
Total consideration	$ 1,884.5
Cash acquired	437.6
Receipts of unrestricted cash, net of payments related to the Business Combination	(333.4)
Ordinary Shares
Business Acquisition [Line Items]
Estimated fair value of Mallinckrodt ordinary shares issued	1,778.4
Share-Based Payment Arrangement
Business Acquisition [Line Items]
Estimated fair value of Mallinckrodt ordinary shares issued	$ 1.9

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