Restructuring and Related Charges (Narrative) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
Sep. 26, 2014
Restructuring Cost and Reserve [Line Items]
Property, plant and equipment asset impairment	$ 25.6
Employee terminations
Restructuring Cost and Reserve [Line Items]
Accelerated share based compensation expense	35.1
2013 Mallinckrodt program \| Minimum
Restructuring Cost and Reserve [Line Items]
2013 Mallinckrodt program expected cost range	100.0
2013 Mallinckrodt program \| Maximum
Restructuring Cost and Reserve [Line Items]
2013 Mallinckrodt program expected cost range	125.0
Consulting costs
Restructuring Cost and Reserve [Line Items]
Restructuring costs	$ 8.5

Amount of reclassification, impairment, donation, or other change to long-lived, physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 360

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (a)

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Amount expected to be recognized in earnings for the specified restructuring cost.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 420

-SubTopic 10

-Section 50

-Paragraph 1

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=6394359&loc=d3e17939-110869

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Staff Accounting Bulletin (SAB)

-Number Topic 5

-Section P

-Subsection 3, 4

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 420

-SubTopic 10

-Section S99

-Paragraph 2

-Subparagraph (SAB Topic 5.P.4(b))

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Amount, after cash payment, of expenses associated with exit or disposal activities pursuant to an authorized plan. Excludes expenses related to a discontinued operation or an asset retirement obligation.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 28

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3602-108585

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Additional share-based compensation cost recognized as a result of an occurrence of an event that accelerates its recognition.

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