Segment and Geographical Data (Schedule of Net Sales and Long-Lived Assets by Geographic Area) (Details) - USD ($) $ in Millions	6 Months Ended			12 Months Ended
	Dec. 30, 2022		Jun. 16, 2022	Dec. 31, 2021		Dec. 25, 2020
Schedule of Net Sales and Long-Lived Assets by Geographic Area [Line Items]
Net sales (includes retrospective one-time charge of $536.0 related to the Medicaid lawsuit for fiscal 2020)	$ 1,039.7		$ 874.6	$ 2,208.8		$ 2,213.4
Long-Lived Assets	468.4			790.2
Medicaid lawsuit						536.0
Sales [Member]
Schedule of Net Sales and Long-Lived Assets by Geographic Area [Line Items]
Medicaid lawsuit	0.0	[1]	0.0	0.0	[1]	536.0	[1]
Operating Segments
Schedule of Net Sales and Long-Lived Assets by Geographic Area [Line Items]
Net sales (includes retrospective one-time charge of $536.0 related to the Medicaid lawsuit for fiscal 2020)	1,039.7		874.6	2,208.8		2,749.4
United States
Schedule of Net Sales and Long-Lived Assets by Geographic Area [Line Items]
Net sales (includes retrospective one-time charge of $536.0 related to the Medicaid lawsuit for fiscal 2020)	928.3	[2]	784.2	1,991.8	[2]	2,465.5	[2]
Long-Lived Assets	287.3			629.3
EMEA
Schedule of Net Sales and Long-Lived Assets by Geographic Area [Line Items]
Net sales (includes retrospective one-time charge of $536.0 related to the Medicaid lawsuit for fiscal 2020)	100.4	[2]	73.6	181.8	[2]	227.5	[2]
Long-Lived Assets	178.0			156.2
Other Countries
Schedule of Net Sales and Long-Lived Assets by Geographic Area [Line Items]
Net sales (includes retrospective one-time charge of $536.0 related to the Medicaid lawsuit for fiscal 2020)	11.0	[2]	$ 16.8	35.2	[2]	$ 56.4	[2]
Other Address
Schedule of Net Sales and Long-Lived Assets by Geographic Area [Line Items]
Long-Lived Assets	3.1			4.7
IRELAND
Schedule of Net Sales and Long-Lived Assets by Geographic Area [Line Items]
Long-Lived Assets	$ 174.9			$ 154.5

[1] Specialty Brands net sales for fiscal 2020 (Predecessor) includes the prospective change to the Medicaid rebate calculation, which served to reduce Acthar Gel net sales by $40.4 million for the period from June 15, 2020 through December 25, 2020 (Predecessor).

[2] Net sales are attributed to regions based on the location of the entity that records the transaction, none of which relate to the country of Ireland.