Restructuring and Related Charges (Schedule of Net Restructuring and Related Charges) (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Mar. 25, 2016	Mar. 27, 2015	Mar. 25, 2016	Mar. 27, 2015
Restructuring Cost and Reserve [Line Items]
Restructuring and related charges, net	$ 10.4	$ 3.6	$ 16.8	$ 10.9
Less: non-cash charges, including accelerated share-based compensation expense	(1.7)	(1.0)	(1.8)	(7.9)
Total charges expected to be settled in cash	8.7	2.6	15.0	3.0
2013 Mallinckrodt program
Restructuring Cost and Reserve [Line Items]
Restructuring and related charges, net	8.4	2.7	14.1	(2.2)
Acquisitions
Restructuring Cost and Reserve [Line Items]
Restructuring and related charges, net	$ 2.0	0.9	$ 2.7	13.1
Severance
Restructuring Cost and Reserve [Line Items]
Accelerated share-based compensation expense		$ 0.9		$ 7.7