Financial Instruments and Fair Value Measurements (Narrative) (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 28, 2018	Mar. 30, 2018	Sep. 28, 2018	Mar. 16, 2018	Dec. 29, 2017	Apr. 30, 2013
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Business Combination, Contingent Consideration, Liability, Current	$ 52.8		$ 52.8
Business Combination, Contingent Consideration, Liability, Noncurrent	114.5		114.5
Mesoblast [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Proceeds from Sale of Available-for-sale Securities, Equity			25.5
Available-for-sale Securities, Gross Realized Gains (Losses), Sale Proceeds			3.4
Senior Notes | 3.50% Senior Notes
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Stated interest rate						3.50%
Senior Notes | 4.75% Senior Notes
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Stated interest rate						4.75%
Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Investments, Fair Value Disclosure	35.3		35.3		$ 35.4
PreveLeak | Hemostasis Products
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Business Combination, Contingent Consideration, Payment		$ 12.0
Level 3 | Other Assets
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Cash surrender value of life insurance	66.1		66.1		67.0
Level 3 | Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Investments, Fair Value Disclosure	0.0		0.0		0.0
Level 3 | Recurring | Questcor Pharmaceuticals, Inc.
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Fair value of contingent liability	86.7		86.7		111.8
Level 3 | Recurring | Stratatech
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Fair value of contingent liability	56.9		56.9		53.5
Level 3 | Raplixa | Recurring | Hemostasis Products
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Fair value of contingent consideration					7.0
Level 3 | PreveLeak | Recurring | Hemostasis Products
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Fair value of contingent liability					17.1
Level 3 | Stannsoporfin [Member] | Recurring | InfaCare Acquisition
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Fair value of contingent consideration	0.0		0.0		35.0
Fair value adjustment	7.0		35.0
Level 3 | MNK-6105 [Member] | Recurring | Ocera [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Fair value of contingent consideration	$ 23.7		$ 23.7		22.0
Level 2 | Debentures | 8.00% Debenture
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Stated interest rate	8.00%		8.00%
Level 2 | Debentures | 9.50% Debenture
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Stated interest rate	9.50%		9.50%
Level 2 | Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Investments, Fair Value Disclosure	$ 10.8		$ 10.8		11.4
Level 1 | Senior Notes | 3.50% Senior Notes
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Stated interest rate	3.50%		3.50%
Level 1 | Senior Notes | 4.75% Senior Notes
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Stated interest rate	4.75%		4.75%
Level 1 | Senior Notes | 5.75% Senior Notes
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Stated interest rate	5.75%		5.75%
Level 1 | Senior Notes | 4.88% Senior Notes
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Stated interest rate	4.875%		4.875%
Level 1 | Senior Notes | 5.50% Senior Notes
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Stated interest rate	5.50%		5.50%
Level 1 | Unsecured Debt | 5.625% Senior Notes
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Stated interest rate	5.625%		5.625%
Level 1 | Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Investments, Fair Value Disclosure	$ 24.5		$ 24.5		24.0
Maximum | Synacthen | Questcor Pharmaceuticals, Inc.
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Milestone Payment			115.0
Hemostasis Products
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Disposal Group, Not Discontinued Operation, Contingent Consideration				$ 12.1
Nuclear Imaging
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Contingent consideration received, equity certificates			9.0
Nuclear Imaging | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Contingent consideration received, equity certificates	9.0
Indemnification Agreement | Mallinckrodt Baker | Level 1 | Other Assets
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Restricted Cash and Cash Equivalents	$ 18.5		18.5		$ 18.3
Novartis 2015 and 2016 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Business Combination, Contingent Consideration, Annual Payments			$ 25.0