Condensed Consolidating Financial Statements (Schedule of Condensed Consolidating Statements of Comprehensive Income) (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 24, 2016	Jun. 30, 2017	Jun. 24, 2016
Condensed Consolidating Financial Statements
Net sales	$ 824.5	$ 866.6	$ 1,635.4	$ 1,682.4
Cost of sales	408.4	377.8	800.7	768.5
Gross profit	416.1	488.8	834.7	913.9
Selling, general and administrative expenses	232.1	224.9	540.2	434.2
Research and development expenses	69.2	74.8	131.4	132.9
Restructuring charges, net	0.6	14.0	17.8	22.4
Non-restructuring impairment charges	0.0	0.0	0.0	16.9
Losses (gains) on divestiture and license	2.1	0.0	(57.0)	0.0
Operating income	112.1	175.1	202.3	307.5
Interest expense	(92.2)	(95.6)	(186.4)	(192.8)
Interest income	0.6	0.4	1.5	0.6
Other income (expense), net	10.0	(1.3)	2.5	(2.0)
Intercompany Interest And Fees	0.0	0.0	0.0	0.0
Income (Loss) from Equity Method Investments	0.0	0.0	0.0	0.0
Income from continuing operations before income taxes	30.5	78.6	19.9	113.3
Income tax benefit	(40.1)	(98.1)	(79.6)	(161.9)
Income (Loss) from Continuing Operations	70.6	176.7	99.5	275.2
(Loss) income from discontinued operations, net of income taxes	(7.8)	22.6	362.5	42.4
Net Income (Loss)	62.8	199.3	462.0	317.6
Other Comprehensive Income (Loss), Net of Tax	1.9	(0.6)	64.5	(0.4)
Comprehensive Income (Loss)	64.7	198.7	526.5	317.2
Mallinckrodt plc
Condensed Consolidating Financial Statements
Net sales	0.0	0.0	0.0	0.0
Cost of sales	0.9	0.0	0.9	0.0
Gross profit	(0.9)	0.0	(0.9)	0.0
Selling, general and administrative expenses	15.1	12.3	33.3	26.2
Research and development expenses	1.8	0.0	1.8	0.0
Restructuring charges, net	0.0	0.0	0.0	0.0
Non-restructuring impairment charges	0.0	0.0	0.0	0.0
Losses (gains) on divestiture and license	0.0	0.0	0.0	0.0
Operating income	(17.8)	(12.3)	(36.0)	(26.2)
Interest expense	(3.4)	(56.3)	(6.7)	(126.2)
Interest income	2.0	0.0	3.1	0.0
Other income (expense), net	2.2	2.6	17.6	14.9
Intercompany Interest And Fees	(3.5)	(4.5)	(9.0)	(7.3)
Income (Loss) from Equity Method Investments	81.0	260.2	489.7	452.7
Income from continuing operations before income taxes	60.5	189.7	458.7	307.9
Income tax benefit	(1.3)	(9.6)	(3.3)	(9.7)
Income (Loss) from Continuing Operations	61.8	199.3	462.0	317.6
(Loss) income from discontinued operations, net of income taxes	1.0	0.0	0.0	0.0
Net Income (Loss)	62.8	199.3	462.0	317.6
Other Comprehensive Income (Loss), Net of Tax	1.9	(0.6)	64.5	(0.4)
Comprehensive Income (Loss)	64.7	198.7	526.5	317.2
Mallinckrodt International Finance S.A.
Condensed Consolidating Financial Statements
Net sales	0.0	0.0	0.0	0.0
Cost of sales	0.0	0.0	0.0	0.0
Gross profit	0.0	0.0	0.0	0.0
Selling, general and administrative expenses	0.2	0.2	0.4	0.4
Research and development expenses	0.0	0.0	0.0	0.0
Restructuring charges, net	0.0	0.0	0.0	0.0
Non-restructuring impairment charges	0.0	0.0	0.0	0.0
Losses (gains) on divestiture and license	0.0	0.0	0.0	0.0
Operating income	(0.2)	(0.2)	(0.4)	(0.4)
Interest expense	(88.7)	(81.6)	(174.0)	(163.1)
Interest income	0.3	0.1	0.6	0.3
Other income (expense), net	6.6	0.1	(3.3)	0.0
Intercompany Interest And Fees	0.0	0.0	0.0	0.1
Income (Loss) from Equity Method Investments	254.7	380.5	851.7	712.5
Income from continuing operations before income taxes	172.7	298.9	674.6	549.4
Income tax benefit	(0.2)	(10.2)	(0.5)	(14.0)
Income (Loss) from Continuing Operations	172.9	309.1	675.1	563.4
(Loss) income from discontinued operations, net of income taxes	0.0	(0.2)	(1.7)	(1.7)
Net Income (Loss)	172.9	308.9	673.4	561.7
Other Comprehensive Income (Loss), Net of Tax	1.9	(0.6)	64.5	(0.4)
Comprehensive Income (Loss)	174.8	308.3	737.9	561.3
Other Subsidiaries
Condensed Consolidating Financial Statements
Net sales	824.5	866.6	1,635.4	1,682.4
Cost of sales	407.5	377.8	799.8	768.5
Gross profit	417.0	488.8	835.6	913.9
Selling, general and administrative expenses	216.8	212.4	506.5	407.6
Research and development expenses	67.4	74.8	129.6	132.9
Restructuring charges, net	0.6	14.0	17.8	22.4
Non-restructuring impairment charges	0.0	0.0	0.0	16.9
Losses (gains) on divestiture and license	2.1	0.0	(57.0)	0.0
Operating income	130.1	187.6	238.7	334.1
Interest expense	(18.7)	(20.3)	(38.9)	(42.0)
Interest income	16.9	62.9	31.0	138.8
Other income (expense), net	1.2	(4.0)	(11.8)	(16.9)
Intercompany Interest And Fees	3.5	4.5	9.0	7.2
Income (Loss) from Equity Method Investments	172.9	308.9	673.4	561.7
Income from continuing operations before income taxes	305.9	539.6	901.4	982.9
Income tax benefit	(38.6)	(78.3)	(75.8)	(138.2)
Income (Loss) from Continuing Operations	344.5	617.9	977.2	1,121.1
(Loss) income from discontinued operations, net of income taxes	(8.8)	22.8	364.2	44.1
Net Income (Loss)	335.7	640.7	1,341.4	1,165.2
Other Comprehensive Income (Loss), Net of Tax	3.4	(1.4)	128.4	(1.2)
Comprehensive Income (Loss)	339.1	639.3	1,469.8	1,164.0
Eliminations
Condensed Consolidating Financial Statements
Net sales	0.0	0.0	0.0	0.0
Cost of sales	0.0	0.0	0.0	0.0
Gross profit	0.0	0.0	0.0	0.0
Selling, general and administrative expenses	0.0	0.0	0.0	0.0
Research and development expenses	0.0	0.0	0.0	0.0
Restructuring charges, net	0.0	0.0	0.0	0.0
Non-restructuring impairment charges	0.0	0.0	0.0	0.0
Losses (gains) on divestiture and license	0.0	0.0	0.0	0.0
Operating income	0.0	0.0	0.0	0.0
Interest expense	18.6	62.6	33.2	138.5
Interest income	(18.6)	(62.6)	(33.2)	(138.5)
Other income (expense), net	0.0	0.0	0.0	0.0
Intercompany Interest And Fees	0.0	0.0	0.0	0.0
Income (Loss) from Equity Method Investments	(508.6)	(949.6)	(2,014.8)	(1,726.9)
Income from continuing operations before income taxes	(508.6)	(949.6)	(2,014.8)	(1,726.9)
Income tax benefit	0.0	0.0	0.0	0.0
Income (Loss) from Continuing Operations	(508.6)	(949.6)	(2,014.8)	(1,726.9)
(Loss) income from discontinued operations, net of income taxes	0.0	0.0	0.0	0.0
Net Income (Loss)	(508.6)	(949.6)	(2,014.8)	(1,726.9)
Other Comprehensive Income (Loss), Net of Tax	(5.3)	2.0	(192.9)	1.6
Comprehensive Income (Loss)	$ (513.9)	$ (947.6)	$ (2,207.7)	$ (1,725.3)