Segment Data (Schedule of Net Sales from External Customers by Products) (Details) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 27, 2024 USD ($)	Sep. 29, 2023 USD ($)	Sep. 27, 2024 USD ($) Defendent	Sep. 29, 2023 USD ($)
Segment Reporting Information
Net sales	$ 505.5	$ 497.0	$ 1,487.6	$ 1,396.6
Number of Reportable Segments | Defendent			2
Specialty Brands | Operating Segments
Segment Reporting Information
Net sales	286.0	286.2	$ 817.8	818.3
Specialty Generics
Segment Reporting Information
Net sales	219.5	210.8	669.8	578.3
Specialty Generics | Operating Segments
Segment Reporting Information
Net sales	219.5	210.8	669.8	578.3
Acthar | Specialty Brands
Segment Reporting Information
Net sales	126.4	122.1	346.9	320.9
Inomax | Specialty Brands
Segment Reporting Information
Net sales	64.0	72.9	200.6	232.5
Therakos immunotherapy | Specialty Brands
Segment Reporting Information
Net sales	67.6	66.0	193.0	187.6
Amitiza [Member] | Specialty Brands
Segment Reporting Information
Net sales	18.8	18.3	53.5	61.4
Other | Specialty Brands
Segment Reporting Information
Net sales	1.9	2.5	5.2	5.9
Opioids | Specialty Generics
Segment Reporting Information
Net sales	85.9	65.9	263.0	200.2
ADHD | Specialty Generics
Segment Reporting Information
Net sales	41.3	41.5	114.8	82.9
Addiction Treatment | Specialty Generics
Segment Reporting Information
Net sales	18.1	15.1	54.5	46.8
Other Generics | Specialty Generics
Segment Reporting Information
Net sales	0.9	3.4	6.0	7.6
Generics | Specialty Generics
Segment Reporting Information
Net sales	146.2	125.9	438.3	337.5
Controlled substances | Specialty Generics
Segment Reporting Information
Net sales	27.2	22.0	76.5	61.4
APAP | Specialty Generics
Segment Reporting Information
Net sales	40.0	57.4	139.0	163.6
Other API | Specialty Generics
Segment Reporting Information
Net sales	6.1	5.5	16.0	15.8
API | Specialty Generics
Segment Reporting Information
Net sales	73.3	84.9	231.5	240.8
Terlivaz | Specialty Brands
Segment Reporting Information
Net sales	$ 7.3	$ 4.4	$ 18.6	$ 10.0