Restructuring and Related Charges (Schedule of Restructuring Reserves by Type of Cost) (Details) $ in Millions	9 Months Ended
Jun. 26, 2015 USD ($)
Restructuring Reserve [Roll Forward]
Beginning Balance	$ 34.9
Charges	34.7
Changes in estimate	(9.9)
Cash payments	(32.3)
Restructuring Reserve, Reclassification	(2.5)
Currency translation	(0.7)
Ending Balance	24.2
2013 Mallinckrodt program
Restructuring Reserve [Roll Forward]
Beginning Balance	26.6
Charges	9.9
Changes in estimate	(8.3)
Cash payments	(18.9)
Restructuring Reserve, Reclassification	(2.5)
Currency translation	(0.7)
Ending Balance	6.1
Acquisitions
Restructuring Reserve [Roll Forward]
Beginning Balance	7.9
Charges	24.8
Changes in estimate	(1.3)
Cash payments	(13.3)
Restructuring Reserve, Reclassification	0.0
Currency translation	0.0
Ending Balance	18.1
Other
Restructuring Reserve [Roll Forward]
Beginning Balance	0.4
Charges	0.0
Changes in estimate	(0.3)
Cash payments	(0.1)
Restructuring Reserve, Reclassification	0.0
Currency translation	0.0
Ending Balance	$ 0.0

Cash Restructuring Charges

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- Definition

Restructuring Reserve, Reclassification

+ References

No definition available.

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- Definition

Amount of cash payments made as the result of exit or disposal activities. Excludes payments associated with 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)

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- Definition

Carrying amount (including both current and noncurrent portions of the accrual) as of the balance sheet date pertaining to a specified type of cost associated with exit from or disposal of business activities or restructuring pursuant to a duly authorized plan.

+ References

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- Definition

Amount of (expense) reversal of expense related to a previously accrued restructuring cost liability. Excludes adjustments for costs incurred, costs settled, and foreign currency translation adjustments.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

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-Paragraph 1

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-Publisher SEC

-Name Staff Accounting Bulletin (SAB)

-Number Topic 5

-Section P

-Subsection 3, 4

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

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- Definition

Amount of gain (loss) from translating a restructuring reserve to the currency of the reporting entity from an amount denominated or measured in a different currency.

+ References

Reference 1: 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)(2))

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-Number Topic 5

-Section P

-Subsection 3, 4

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