Earnings Per Share (Details) - USD ($) shares in Thousands, $ in Millions	3 Months Ended		6 Months Ended
	Jul. 02, 2016	Jun. 27, 2015	Jul. 02, 2016		Jun. 27, 2015		Oct. 22, 2015
Numerator:
Net income (loss)	$ 194.3	$ 56.4	$ (140.3)		$ (38.4)
Denominator:
Weighted average shares outstanding for basic EPS	143,200	146,300	143,200		143,500
Dilutive effect of share-based awards	400	500	0	[1]	0	[1]
Weighted average shares outstanding for diluted EPS	143,600	146,800	143,200		143,500
Anti-dilutive share-based awards excluded from computation of diluted EPS	1,000	0	0	[1]	0	[1]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period	19	57	98		92
Stock Repurchase Program, Authorized Amount	$ 0.0		$ 0.0
Stock Repurchase Program, Remaining Authorized Repurchase Amount	$ 1,500.0		$ 1,500.0
Perrigo Co PLC [Member]
Denominator:
Stock Repurchase Program, Authorized Amount							$ 2,000.0

[1] In the period of a net loss, diluted shares equal basic shares.