Segment Data (Schedule of Net Sales from External Customers by Products) (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 28, 2018	Sep. 29, 2017	Sep. 28, 2018	Sep. 29, 2017
Segment Reporting Information
Net sales	$ 640.0	$ 600.6	$ 1,844.3	$ 1,760.7
Operating Segments | Specialty Brands
Segment Reporting Information
Net sales	640.0	600.6	1,844.3	1,760.7
Acthar | Operating Segments | Specialty Brands
Segment Reporting Information
Net sales	290.1	308.7	827.1	899.9
Inomax | Operating Segments | Specialty Brands
Segment Reporting Information
Net sales	133.2	125.7	404.0	379.6
Ofirmev | Operating Segments | Specialty Brands
Segment Reporting Information
Net sales	87.1	75.4	254.7	224.5
Therakos immunotherapy | Operating Segments | Specialty Brands
Segment Reporting Information
Net sales	60.0	55.3	174.2	157.7
Amitiza [Member] | Operating Segments | Specialty Brands
Segment Reporting Information
Net sales	48.2	0.0	119.2	0.0
BioVectra Inc [Member] | Operating Segments | Specialty Brands
Segment Reporting Information
Net sales	13.9	16.0	35.7	36.4
Other | Operating Segments | Specialty Brands
Segment Reporting Information
Net sales	$ 7.5	$ 19.5	$ 29.4	$ 62.6