Quarterly Financial Data (unaudited) (Details) - USD ($) $ / shares in Units, shares in Millions	3 Months Ended																				6 Months Ended			12 Months Ended
	Dec. 31, 2016		Oct. 01, 2016		Jul. 02, 2016		Apr. 02, 2016		Dec. 31, 2015		Sep. 26, 2015		Jun. 27, 2015		Mar. 28, 2015		Dec. 27, 2014		Sep. 27, 2014		Oct. 03, 2016	Dec. 31, 2015	Dec. 27, 2014	Dec. 31, 2016	Jun. 27, 2015	Jun. 28, 2014
Net sales	$ 1,331,200,000	[1]	$ 1,261,600,000	[2]	$ 1,340,500,000	[3]	$ 1,347,300,000	[4]	$ 1,359,100,000	[5]	$ 1,273,100,000	[6]	$ 1,415,200,000	[7]	$ 967,200,000	[8]	$ 985,100,000	[9]	$ 859,600,000			$ 2,632,200,000	$ 1,844,700,000	$ 5,280,600,000	$ 4,227,100,000	$ 3,914,100,000
Gross profit	487,700,000	[1]	484,500,000	[2]	546,500,000	[3]	533,100,000	[4]	543,700,000	[5]	535,200,000	[6]	601,000,000	[7]	369,400,000	[8]	369,700,000	[9]	304,100,000			1,078,900,000	673,800,000	2,051,800,000	1,644,200,000	1,452,100,000
Fair Value, Option, Changes in Fair Value, Gain (Loss)	1,115,600,000	[1]	(377,400,000)	[2]	(910,800,000)	[3]	(204,400,000)	[4]	116,600,000	[5]	173,800,000	[6]	(69,200,000)	[7]	100,800,000	[8]	(105,800,000)	[9]	58,900,000			57,300,000	46,900,000	(2,608,200,000)	78,500,000	26,600,000
Net income (loss)	$ (1,359,100,000)	[1]	$ (1,590,200,000)	[2]	$ (534,300,000)	[3]	$ (529,200,000)	[4]	$ (218,400,000)	[5]	$ 260,900,000	[6]	$ (22,200,000)	[7]	$ (22,200,000)	[8]	$ 151,100,000	[9]	$ 29,400,000			$ 42,500,000	$ 180,600,000	$ (4,012,800,000)	$ 136,100,000	$ 232,800,000
Earnings Per Share [Abstract]
Basic (in dollars per share)	$ (9.48)	[1],[10]	$ (11.10)	[2],[10]	$ (3.73)	[3],[10]	$ (3.70)	[4],[10]	$ (1.51)	[5],[10]	$ 1.78	[6],[10]	$ (0.15)	[7],[10]	$ (0.16)	[8],[10]	$ 1.11	[9],[10]	$ 0.22	[10]		$ 0.29	$ 1.34	$ (28.01)	$ 0.97	$ 2.02
Diluted (in dollars per share)	$ (9.48)	[1],[10]	$ (11.10)	[2],[10]	$ (3.73)	[3],[10]	$ (3.70)	[4],[10]	$ (1.51)	[5],[10]	$ 1.78	[6],[10]	$ (0.15)	[7],[10]	$ (0.16)	[8],[10]	$ 1.10	[9],[10]	$ 0.22	[10]		$ 0.29	$ 1.34	$ (28.01)	$ 0.97	$ 2.01
Weighted-average shares outstanding
Basic (in shares)	143.4	[1]	143.3	[2]	143.2	[3]	143.2	[4]	144.9	[5]	146.3	[6]	146.3	[7]	140.8	[8]	136.3	[9]	133.9			145.6	135.1	143.3	139.3	115.1
Diluted (in shares)	143.4	[1]	143.3	[2]	143.2	[3]	143.2	[4]	144.9	[5]	146.9	[6]	146.3	[7]	140.8	[8]	136.8	[9]	134.4			146.1	135.6	143.3	139.8	115.6
Selected Quarterly Financial Information [Abstract]
Intangible asset impairment charge	$ 378,600,000		$ 866,600,000				$ 273,300,000
Goodwill impairment charge	224,100,000		737,900,000				130,500,000															$ 0		$ 1,092,500,000		$ 0
Impairment charge	$ (4,500,000)		10,200,000		$ 10,500,000
Royalty rights - change in fair value					$ 910,800,000
Legal fees									$ 71,300,000		$ 15,600,000		$ 13,400,000
Impairment of intangibles																					$ 849,100,000			849,500,000
Impairment charges																						215,600,000	$ 0	2,631,000,000	$ 6,800,000	6,000,000
Restructuring									24,700,000													26,900,000	4,200,000	31,000,000	5,100,000	47,000,000
Available-for-sale securities, gross realized gain (loss)									10,700,000
Derivative, loss on derivative															$ 258,200,000		$ 64,700,000					0		0	326,400,000	0
Business combination, acquisition related costs													18,500,000				17,800,000
Cost of services, licenses and maintenance agreements													18,000,000				10,000,000
Loss on extinguishment of debt																	9,600,000					$ 900,000	$ 9,600,000	1,100,000	10,500,000	$ 165,800,000
Proceeds from collaborators																	$ 12,500,000
Inventory step-up													$ 15,600,000
Omega
Selected Quarterly Financial Information [Abstract]
Business combination, acquisition related costs															$ 18,600,000
Omega
Selected Quarterly Financial Information [Abstract]
Business combination, acquisition related costs																									$ 387,000,000
Omega | Brands
Selected Quarterly Financial Information [Abstract]
Impairment of intangibles			$ 575,700,000				$ 273,400,000		185,100,000															$ 400,000
Operating expense | Discontinued operations, held-for-sale | API
Selected Quarterly Financial Information [Abstract]
Impairment charges									$ 29,000,000

[1] ncludes intangible asset impairment charges of $378.6 million, goodwill impairment charges of $224.1 million, and a reduction in held-for-sale impairment charges of $4.5 million. September 26, 2015 (2) December 31, 2015 (3)Six Months Ended December 31, 2015Restated RestatedNet sales$1,273.1 $1,359.1Gross profit$535.2 $543.7Tysabri® royalty stream - change in fair value$(173.8) $116.6Net income (loss)$260.9 $(218.4)Income (loss) per share(1): Basic$1.78 $(1.51)Diluted$1.78 $(1.51)Weighted-average shares outstanding Basic146.3 144.9Diluted146.9 144.9

[2] Includes intangible asset impairment charges of $866.6 million, goodwill impairment charges of $737.9 million, and held-for-sale impairment charges of $10.2 million.

[3] Includes held-for-sale impairment charges of $10.5 million and change in fair market value on royalty rights of $910.8 million.

[4] Includes an intangible asset impairment charges of $273.3 million, and a goodwill impairment charge of $130.5 million.

[5] Includes an intangible asset impairment charge of $185.1 million, Mylan defense-related fees of $71.3 million, an impairment charge on our India API held for sale assets of $29.0 million, restructuring charges of $24.7 million, and an investment impairment charge of $10.7 million.

[6] Includes Mylan defense-related fees of $15.6 million.

[7] (4) Includes acquisition costs of $18.5 million, an initial payment made in connection with an R&D agreement of $18.0 million, an inventory step up related to the Omega acquisition totaling $15.6 million, and $13.4 million of Mylan defense-related fees.

[8] Includes losses on derivatives associated with the Omega acquisition of $258.2 million and Omega financing fees of $18.6 million.

[9] Includes losses on derivatives associated with the Omega acquisition of $64.7 million, Omega transaction expenses of $17.8 million, an R&D payment made in connection with a collaborative agreement of $10.0 million, a $9.6 million loss on extinguishment of debt, partially offset by income from transfer of rights agreement of $12.5 million.

[10] The sum of individual per share amounts may not equal due to rounding.