Acquisitions Asset Acquisitions (Details) - USD ($) $ in Millions	12 Months Ended
	Jun. 27, 2015	Jun. 28, 2014	May. 01, 2014	Jun. 29, 2013
Acquired Finite-Lived Intangible Assets [Line Items]
Percent of royalty revenues generated by specific agreement	96.00%
Net sales for royalties	$ 4,603.9	$ 4,060.8		$ 3,539.8
Tysabri [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Percent of royalty revenues generated by specific agreement			12.00%
Finite-lived Intangible Assets Acquired	$ 5,800.0
Noncompete Agreements [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life	2 years
Prialt [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Finite-lived Intangible Assets Acquired	$ 11.0
Distribution And License Agreements [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life	20 years
Developed Technology Rights [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life	12 years
Customer Relationships [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life	20 years
Fera Pharmaceuticals, LLC [Domain] | Developed Technology Rights [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Asset, Useful Life		15 years
Velcera, Inc. [Domain] | Trademarks and Trade Names [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Asset, Useful Life		25 years
Velcera, Inc. [Domain] | Noncompete Agreements [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Asset, Useful Life		3 years
Velcera, Inc. [Domain] | Distribution And License Agreements [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Asset, Useful Life		10 years
Velcera, Inc. [Domain] | Customer Relationships [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Asset, Useful Life		20 years
Rosemont Pharmaceuticals Ltd. [Domain] | Noncompete Agreements [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Asset, Useful Life		3 years
Rosemont Pharmaceuticals Ltd. [Domain] | Distribution And License Agreements [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life		7 years
Rosemont Pharmaceuticals Ltd. [Domain] | Developed Technology Rights [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Asset, Useful Life		14 years
Cobrek Pharmaceuticals, Inc. [Domain] | Developed Technology Rights [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Asset, Useful Life		12 years
Sergeant's Pet Care Products, Inc. [Domain] | Developed Technology Rights [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Asset, Useful Life				10 years
Sergeant's Pet Care Products, Inc. [Domain] | favorable supply agreement [Domain]
Acquired Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Asset, Useful Life				7 years
Sergeant's Pet Care Products, Inc. [Domain] | Customer Relationships [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Asset, Useful Life		20 years
Fera (methazolomide) [Member] | Customer-Related Intangible Assets [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Asset, Useful Life	15 years
Elan Corporation [Member] | Tysabri [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Asset, Useful Life	20 years
Elan Corporation [Member] | Prialt [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Asset, Useful Life	10 years
Minimum [Member] | Tysabri [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Percent of royalty revenues generated by specific agreement	18.00%
Net sales for royalties	$ 2,000.0
Minimum [Member] | Trademarks and Trade Names [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Asset, Useful Life	8 years
Minimum [Member] | Prialt [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Percent of royalty revenues generated by specific agreement	7.00%
Minimum [Member] | Developed Technology Rights [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Asset, Useful Life	4 years
Minimum [Member] | Customer Relationships [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Asset, Useful Life	7 years
Minimum [Member] | Sergeant's Pet Care Products, Inc. [Domain] | Noncompete Agreements [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Asset, Useful Life		1 year
Maximum [Member] | Tysabri [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Percent of royalty revenues generated by specific agreement	25.00%
Net sales for royalties	$ 2,000.0
Maximum [Member] | Trademarks and Trade Names [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Asset, Useful Life	20 years
Maximum [Member] | Prialt [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Percent of royalty revenues generated by specific agreement	17.50%
Maximum [Member] | Developed Technology Rights [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Asset, Useful Life	13 years
Maximum [Member] | Customer Relationships [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Asset, Useful Life	21 years
Maximum [Member] | Sergeant's Pet Care Products, Inc. [Domain] | Noncompete Agreements [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Asset, Useful Life		3 years