Restructuring and Related Charges (Narrative) (Details) - USD ($) $ in Millions	1 Months Ended	3 Months Ended	6 Months Ended			11 Months Ended	12 Months Ended
	Dec. 29, 2023	Jun. 28, 2024	Jun. 28, 2024	Dec. 30, 2022	Jun. 16, 2022	Nov. 14, 2023	Dec. 27, 2024	Dec. 01, 2021	Feb. 01, 2018
Restructuring Cost and Reserve [Line Items]
Restructuring charges, net	$ 0.0			$ 11.1	$ 9.6	$ 0.9	$ 10.5
StrataGraft [Member]
Restructuring Cost and Reserve [Line Items]
Other Nonrecurring Gain							$ 2.5
Gain (Loss) on Termination of Lease			$ 5.1
Lease Termination Penalty		$ 2.6
2018 Program | Minimum
Restructuring Cost and Reserve [Line Items]
Mallinckrodt program expected cost range									$ 100.0
2018 Program | Maximum
Restructuring Cost and Reserve [Line Items]
Mallinckrodt program expected cost range									$ 125.0
Restructuring Fiscal 2021 Plan | Minimum
Restructuring Cost and Reserve [Line Items]
Mallinckrodt program expected cost range								$ 50.0
Restructuring Fiscal 2021 Plan | Maximum
Restructuring Cost and Reserve [Line Items]
Mallinckrodt program expected cost range								$ 100.0