- Additional Information (Details) - USD ($) $ in Millions		3 Months Ended																			6 Months Ended		12 Months Ended
	Mar. 30, 2015	Dec. 31, 2016		Oct. 01, 2016	[2]	Jul. 02, 2016	[3]	Apr. 02, 2016	[4]	Dec. 31, 2015		Sep. 26, 2015	[6]	Jun. 27, 2015		Mar. 28, 2015	[8]	Dec. 27, 2014	[9]	Sep. 27, 2014	Dec. 31, 2015	Dec. 27, 2014	Dec. 31, 2016	Jun. 27, 2015	Jun. 28, 2014
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Non-current deferred income taxes		$ 389.9								$ 1,372.7				$ 1,514.3							$ 1,372.7		$ 389.9	$ 1,514.3	$ 732.6
Net income		(1,359.1)	[1]	$ (1,590.2)		$ (534.3)		$ (529.2)		(218.4)	[5]	$ 260.9		(22.2)	[7]	$ (22.2)		$ 151.1		$ 29.4	42.5	$ 180.6	(4,012.8)	136.1	232.8
Foreign currency translation adjustments																					(135.5)		(63.3)	(33.5)	83.8
Customer related accruals and allowances		484.3								489.4				459.2							489.4		484.3	459.2
Accounts receivable		1,176.0								1,189.0				1,209.4							1,189.0		1,176.0	1,209.4	931.5
Depreciation																					53.8		100.2	84.3	77.9
Research and development																					88.2	$ 89.8	184.0	187.8	152.5
Advertising expense																					77.5		155.9	55.7	41.4
Acquisitions of businesses, net of cash acquired																					791.6		427.4	2,177.8	1,605.8
Tysabri® | Royalty rights
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Accounts receivable		84.4								$ 83.4				$ 80.8							83.4		84.4	80.8
Adjustments | Amount of error gross of tax
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Non-current deferred income taxes		$ (236.3)																					$ (236.3)
Adjustments | Tysabri Royalty Stream Fair Value Option Adjustments and Other Misstatements
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Net income																					$ 36.9			$ 8.1	$ 27.5
Omega Restated
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Effective date of acquisition	Mar. 30, 2015
Foreign Exchange Forward
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Maximum remaining maturity of foreign currency derivatives																							18 months
Machinery and Equipment | Minimum
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Property, plant and equipment useful life																							2 years
Machinery and Equipment | Maximum
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Property, plant and equipment useful life																							15 years
Building | Minimum
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Property, plant and equipment useful life																							10 years
Building | Maximum
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Property, plant and equipment useful life																							45 years
CHCI
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Percentage of advertising attributable to segment																					93.00%
Accounting Standards Update 2016-15
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Acquisitions of businesses, net of cash acquired																							$ 2.6

[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.