Earnings Per Share (Details) - USD ($) $ in Millions		3 Months Ended		9 Months Ended
		Oct. 01, 2016	Sep. 26, 2015	Oct. 01, 2016	Sep. 26, 2015	Oct. 22, 2015
Numerator:
Net income (loss)		$ (1,255.2)	$ 112.6	$ (1,395.4)	$ 74.2
Denominator:
Weighted average shares outstanding for basic EPS		143,300,000	146,300,000	143,200,000	144,400,000
Dilutive effect of share-based awards	[1]	0	600,000	0	600,000
Weighted average shares outstanding for diluted EPS		143,300,000	146,900,000	143,200,000	145,000,000
Share-based compensation arrangement by share-based payment award, options, exercises in period		185,000	154,000	283,000	246,000
Stock repurchase program, authorized amount		$ 0.0		$ 0.0
Stock repurchase program, remaining authorized repurchase amount		$ 1,500.0		$ 1,500.0
Anti-dilutive share-based awards excluded from computation of diluted EPS		0	100,000	0	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.