Goodwill and Intangible Assets Narrative (Details) - USD ($) $ / shares in Units, $ in Millions	1 Months Ended	6 Months Ended		11 Months Ended	12 Months Ended
	Dec. 29, 2023	Dec. 30, 2022	Jun. 16, 2022	Nov. 14, 2023	Dec. 31, 2021
Goodwill and Intangible Assets Disclosure [Abstract]
Intangible asset amortization	$ 16.2	$ 318.7	$ 281.8	$ 449.6	$ 581.1
Finite-Lived Intangible Assets [Line Items]
Other Asset Impairment Charges	2.6	0.0	0.0	135.9	154.9
Intangible Assets, Net (Excluding Goodwill)	608.4	2,843.8
Intangible asset amortization	$ 16.2	$ 318.7	$ 281.8	$ 449.6	$ 581.1
Loss from continuing operations	$ (1.94)	$ (45.43)	$ (3.70)	$ (122.75)	$ (8.54)
Finite-lived intangible assets, gross				$ 624.6
Completed Technology
Finite-Lived Intangible Assets [Line Items]
Finite-lived intangible assets, gross	$ 624.6	$ 3,041.2
Reorganization, Chapter11, Post Adjustment, Successor
Finite-Lived Intangible Assets [Line Items]
Intangible Assets, Net (Excluding Goodwill)			$ 3,152.2	624.6
Specialty Brands [Member]
Finite-Lived Intangible Assets [Line Items]
Other Asset Impairment Charges					$ 154.9
Specialty Generics [Member]
Finite-Lived Intangible Assets [Line Items]
Other Asset Impairment Charges				85.8
StrataGraft [Member] | Specialty Brands [Member]
Finite-Lived Intangible Assets [Line Items]
Other Asset Impairment Charges				50.1
StrataGraft PRV
Finite-Lived Intangible Assets [Line Items]
Other Indefinite-lived Intangible Assets			100.0
StrataGraft PRV | Mallinckrodt
Finite-Lived Intangible Assets [Line Items]
Proceeds from Sale of Intangible Assets		65.0
StrataGraft PRV | General Unsecured Claims Trust
Finite-Lived Intangible Assets [Line Items]
Proceeds from Sale of Intangible Assets		$ 35.0
Amitiza
Finite-Lived Intangible Assets [Line Items]
Finite-lived intangible assets, gross				12.3
Amitiza | Change in Accounting Method Accounted for as Change in Estimate
Goodwill and Intangible Assets Disclosure [Abstract]
Intangible asset amortization			21.7
Finite-Lived Intangible Assets [Line Items]
Intangible asset amortization			$ 21.7
Loss from continuing operations			$ 0.26
Amitiza | Specialty Generics [Member]
Finite-Lived Intangible Assets [Line Items]
Other Asset Impairment Charges					90.4
Terlivaz
Finite-Lived Intangible Assets [Line Items]
Finite-lived intangible assets, gross				$ 68.1
MNK-6105 [Member] | Specialty Brands [Member]
Finite-Lived Intangible Assets [Line Items]
Other Asset Impairment Charges					$ 64.5