Fair Value Measurements - Additional Information (Details)				3 Months Ended						6 Months Ended	12 Months Ended
	Mar. 27, 2017 USD ($)	Feb. 01, 2017 USD ($)	Dec. 18, 2013	Apr. 01, 2017 USD ($)	Dec. 31, 2016 USD ($)	Oct. 01, 2016 USD ($)	Jul. 02, 2016 USD ($)	Apr. 02, 2016 USD ($)	Dec. 31, 2015 USD ($)	Oct. 03, 2016	Dec. 31, 2016 USD ($) segments	May 01, 2014	Nov. 08, 2013 USD ($)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Transfers between levels				$ 0				$ 0
Net gain on reduction of contingent consideration								16,500,000
Loss on reduction of contingent consideration								2,100,000
Number of reporting units | segments											7
Average growth rate									3.40%	2.00%
Tysabri® royalty stream				(17,100,000)	$ (1,100,000,000)	$ 377,400,000	$ 910,800,000	204,400,000
Goodwill impairment charge								130,500,000
Definite lived asset impairment								273,400,000
Goodwill				4,076,100,000	4,049,400,000						$ 4,049,400,000
Senior notes				5,383,200,000	5,373,100,000						5,373,100,000		$ 2,300,000,000
Proceeds from sale of business and other assets		$ 7,700,000		25,300,000				$ 0
Royalty Pharma contingent milestone payments				184,500,000
Specialty Sciences
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Gain on sale of unit	$ 17,100,000
CHCI
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Goodwill				$ 1,085,600,000	1,070,800,000						1,070,800,000
Omega | Brands
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Definite lived asset impairment											1,500,000,000
Elan
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Effective date of acquisition			Dec. 18, 2013
Public Bonds and Private Placement
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Senior notes									$ 4,600,000,000
Public Bonds and Private Placement | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value of fixed-rate long-term debt					4,600,000,000						4,600,000,000
Retail Bonds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Long term debt					783,200,000				773,100,000		783,200,000
Unamortized debt premium					43,400,000				49,800,000		43,400,000
Retail Bonds | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value of fixed-rate long-term debt					833,000,000				$ 825,000,000		$ 833,000,000
Tysabri®
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Percent of royalty revenues generated by specific agreement												12.00%
Minimum | Tysabri®
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Percent of royalty revenues generated by specific agreement											18.00%
Net sales											$ 2,000,000,000
Maximum | Tysabri®
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Percent of royalty revenues generated by specific agreement											25.00%
Net sales											$ 2,000,000,000
Goodwill | Minimum
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Discount rate											7.00%
Long-term growth rates											2.00%
Goodwill | Maximum
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Discount rate											14.50%
Long-term growth rates											3.00%
Royalty Pharma
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Sale price of divestiture - cash plus non-cash	2,850,000,000
Proceeds from sale of business and other assets	2,200,000,000
Proceeds from sale of business, maximum milestone payments in year two	250,000,000
Proceeds from sale of business, maximum milestone payments in year four	$ 400,000,000
Volatility rate				30.00%
Rate of return				8.05%
Royalties receivable					$ 84,400,000						$ 84,400,000