Fair Value Measurements - Valuation of Financial Instruments Carried at Fair Value (Details) - USD ($) $ in Millions		3 Months Ended		9 Months Ended
		Oct. 01, 2016	Apr. 02, 2016	Oct. 01, 2016	Jul. 02, 2016	Dec. 31, 2015	Sep. 26, 2015	Jun. 27, 2015	Dec. 27, 2014
Assets:
Tysabri® royalty stream - at fair value (restated)		$ 3,550.0		$ 3,550.0		$ 5,310.0
Liabilities:
Goodwill, impairment charges				868.5
Finite-lived intangible assets, carrying amount		4,325.9		4,325.9		3,705.3
Measured on a recurring basis
Assets:
Tysabri® royalty stream - at fair value (restated)		3,550.0		3,550.0		5,310.0
Measured on a recurring basis | Level 1
Assets:
Investment securities		53.0		53.0		14.9
Measured on a recurring basis | Level 2
Assets:
Foreign currency forward contracts		5.2		5.2		4.8
Funds associated with Israeli post-employment benefits		16.5		16.5		17.2
Total level 2 assets		21.7		21.7		22.0
Liabilities:
Interest rate swap agreements		0.0		0.0		0.3
Foreign currency forward contracts		0.8		0.8		3.9
Total level 2 liabilities		0.8		0.8		4.2
Measured on a recurring basis | Level 3 | Contingent consideration classified as equity
Liabilities:
Contingent consideration		75.0		75.0	$ 44.9	17.9	$ 0.0	$ 0.0	$ 12.4
Measured on a non-recurring basis | Level 3
Assets:
Goodwill, fair value	[1]	969.5		969.5		0.0
Indefinite-lived intangible assets	[2]					1,031.8
Definite-lived intangible assets	[3]	66.9		66.9		0.0
Assets held for sale, net		14.1		14.1		37.5
Total level 2 assets		1,722.9		1,722.9		$ 1,069.3
BCH
Liabilities:
Goodwill, carrying amount		1,700.0		1,700.0
Goodwill, impairment charges		737.9		868.5
Indefinite-lived intangible assets, carrying amount		1,200.0		1,200.0
Finite-lived intangible assets, carrying amount		357.8		357.8
Omega
Liabilities:
Finite-lived intangible assets, impairment charges				185.1
Brands | Omega
Liabilities:
Indefinite-lived intangible assets, impairment charges		575.7	$ 273.4	849.1
Finite-lived intangible assets, impairment charges		$ 290.9		$ 290.2

[1] (1)Goodwill with a carrying amount of $1.7 billion was written down to its implied fair value of $1.0 billion, resulting in an impairment charge of $737.9 million for the three months ended October 1, 2016; impairment charges totaled $868.5 million for the nine months ended October 1, 2016 and are included in Impairment charges on the Condensed Consolidated Statements of Operations.

[2] (2)Indefinite-lived intangible assets with a carrying amount of $1.2 billion were written down to a fair value of $672.4 million resulting in total impairment charges of $575.7 million for the three months ended October 1, 2016; impairment charges totaled $849.1 million for the nine months ended October 1, 2016 and are included in Impairment charges on the Condensed Consolidated Statements of Operations.

[3] (3)Definite-lived intangible assets with a carrying amount of $357.8 million were written down to a fair value of $66.9 million resulting in an impairment charge of $290.9 million for the three and nine months ended October 1, 2016, which is included in Impairment charges on the Condensed Consolidated Statements of Operations.