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Goodwill and Intangible Assets (Narrative) (Details) - USD ($) $ / shares in Units, $ in Millions		3 Months Ended			9 Months Ended
	Mar. 14, 2014	Sep. 27, 2019	Jun. 28, 2019	Sep. 28, 2018	Sep. 27, 2019	Sep. 28, 2018	Dec. 28, 2018
Goodwill
Non-restructuring impairment charges		$ 0.0		$ 2.0	$ 113.5	$ 2.0
Amortization of Intangible Assets		210.4		184.2	649.8	546.5
Indefinite-lived Intangible Assets (Excluding Goodwill)		$ 554.8			$ 554.8		$ 668.3
Ofirmev
Goodwill
New Accounting Pronouncement or Change in Accounting Principle, Effect of Change on Basic Earnings Per Share		$ 0.28			$ 1.07
Amortization of Intangible Assets [Member] \| Ofirmev
Goodwill
New Accounting Pronouncement or Change in Accounting Principle, Effect of Change on Operating Results		$ 23.8			$ 89.5
InfaCare [Member] \| Stannsoporfin [Member]
Goodwill
Non-restructuring impairment charges			$ 113.5
Sucampo [Member]
Goodwill
Amortization of Intangible Assets				$ 18.0		$ 45.0
Sucampo [Member] \| VTS-270 [Member]
Goodwill
Indefinite-lived Intangible Assets (Excluding Goodwill)		$ 274.5			$ 274.5
Cadence Pharmaceuticals, Inc. [Member] \| Ofirmev
Goodwill
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life	8 years