Segment and Geographical Data (Schedule of Net Sales from External Costumers by Product) (Details) - USD ($) $ in Millions	6 Months Ended			12 Months Ended
	Dec. 30, 2022		Jun. 16, 2022	Dec. 31, 2021		Dec. 25, 2020
Segment Reporting Information [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
Medicaid lawsuit						536.0
Sales [Member]
Segment Reporting Information [Line Items]
Medicaid lawsuit	0.0	[1]	0.0	0.0	[1]	536.0	[1]
Operating Segments
Segment Reporting Information [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
Operating Segments | Specialty Brands [Member]
Segment Reporting Information [Line Items]
Net sales (includes retrospective one-time charge of $536.0 related to the Medicaid lawsuit for fiscal 2020)	682.4	[1]	587.1	1,547.0	[1]	2,059.6	[1]
Operating Segments | Specialty Generics [Member]
Segment Reporting Information [Line Items]
Net sales (includes retrospective one-time charge of $536.0 related to the Medicaid lawsuit for fiscal 2020)	357.3		287.5	661.8		689.8
Corporate, Non-Segment
Segment Reporting Information [Line Items]
Medicaid lawsuit	0.0	[1]	0.0	0.0	[1]	(641.1)
Acthar Gel (1) | Operating Segments | Specialty Brands [Member]
Segment Reporting Information [Line Items]
Net sales (includes retrospective one-time charge of $536.0 related to the Medicaid lawsuit for fiscal 2020)	294.1	[2]	221.9	593.6	[2]	767.9	[2]
Inomax | Operating Segments | Specialty Brands [Member]
Segment Reporting Information [Line Items]
Net sales (includes retrospective one-time charge of $536.0 related to the Medicaid lawsuit for fiscal 2020)	173.9		165.8	448.5		574.1
Ofirmev | Operating Segments | Specialty Brands [Member]
Segment Reporting Information [Line Items]
Net sales (includes retrospective one-time charge of $536.0 related to the Medicaid lawsuit for fiscal 2020)	(0.3)		2.5	28.9		276.5
Therakos | Operating Segments | Specialty Brands [Member]
Segment Reporting Information [Line Items]
Net sales (includes retrospective one-time charge of $536.0 related to the Medicaid lawsuit for fiscal 2020)	130.5		109.6	266.5		238.6
Amitiza | Operating Segments | Specialty Brands [Member]
Segment Reporting Information [Line Items]
Net sales (includes retrospective one-time charge of $536.0 related to the Medicaid lawsuit for fiscal 2020)	77.1	[3]	81.5	196.9	[3]	188.8	[3]
Other Products | Operating Segments | Specialty Brands [Member]
Segment Reporting Information [Line Items]
Net sales (includes retrospective one-time charge of $536.0 related to the Medicaid lawsuit for fiscal 2020)	7.1		5.8	12.6		13.7
Opioids | Specialty Generics [Member]
Segment Reporting Information [Line Items]
Net sales (includes retrospective one-time charge of $536.0 related to the Medicaid lawsuit for fiscal 2020)	117.9		88.8	213.2		233.9
ADHD | Specialty Generics [Member]
Segment Reporting Information [Line Items]
Net sales (includes retrospective one-time charge of $536.0 related to the Medicaid lawsuit for fiscal 2020)	28.4		17.5	37.4		48.3
Addiction Treatment | Specialty Generics [Member]
Segment Reporting Information [Line Items]
Net sales (includes retrospective one-time charge of $536.0 related to the Medicaid lawsuit for fiscal 2020)	35.0		30.0	68.3		68.9
Other Generics | Specialty Generics [Member]
Segment Reporting Information [Line Items]
Net sales (includes retrospective one-time charge of $536.0 related to the Medicaid lawsuit for fiscal 2020)	6.8		4.9	12.0		7.3
Generics | Specialty Generics [Member]
Segment Reporting Information [Line Items]
Net sales (includes retrospective one-time charge of $536.0 related to the Medicaid lawsuit for fiscal 2020)	188.1		141.2	330.9		358.4
Controlled substances | Specialty Generics [Member]
Segment Reporting Information [Line Items]
Net sales (includes retrospective one-time charge of $536.0 related to the Medicaid lawsuit for fiscal 2020)	47.0		37.6	93.4		98.3
APAP | Specialty Generics [Member]
Segment Reporting Information [Line Items]
Net sales (includes retrospective one-time charge of $536.0 related to the Medicaid lawsuit for fiscal 2020)	111.4		96.5	215.9		213.0
Other API | Specialty Generics [Member]
Segment Reporting Information [Line Items]
Net sales (includes retrospective one-time charge of $536.0 related to the Medicaid lawsuit for fiscal 2020)	10.8		12.2	21.6		20.1
API | Specialty Generics [Member]
Segment Reporting Information [Line Items]
Net sales (includes retrospective one-time charge of $536.0 related to the Medicaid lawsuit for fiscal 2020)	$ 169.2		$ 146.3	$ 330.9		$ 331.4

[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] Fiscal 2020 (Predecessor) includes the prospective change to the Medicaid rebate calculation of $40.4 million for the period from June 15, 2020 through December 25, 2020 (Predecessor).

[3] Amitiza net sales consist of both product and royalty net sales. Refer to Note 5 for further details on Amitiza's revenues.