Restructuring and Related Charges (Schedule of Restructuring Reserves by Type of Cost) (Details) $ in Millions	6 Months Ended
Mar. 25, 2016 USD ($)
Restructuring Reserve [Roll Forward]
Beginning Balance	$ 18.0
Charges	16.0
Changes in estimate	(1.0)
Cash payments	(16.6)
Restructuring Adjustment, Other	(1.4)
Ending Balance	15.0
2013 Mallinckrodt program
Restructuring Reserve [Roll Forward]
Beginning Balance	8.0
Charges	12.5
Changes in estimate	(0.2)
Cash payments	(7.9)
Restructuring Adjustment, Other	(1.4)
Ending Balance	11.0
Acquisitions
Restructuring Reserve [Roll Forward]
Beginning Balance	10.0
Charges	3.5
Changes in estimate	(0.8)
Cash payments	(8.7)
Restructuring Adjustment, Other	0.0
Ending Balance	$ 4.0

Restructuring Adjustment, Other

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- Definition

Cash Restructuring Charges

+ References

No definition available.

+ Details

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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)
-URI http://asc.fasb.org/extlink&oid=56944662&loc=d3e3602-108585

+ Details

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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

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))
-URI http://asc.fasb.org/extlink&oid=27011515&loc=d3e140904-122747

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Staff Accounting Bulletin (SAB)
-Number Topic 5
-Section P
-Subsection 3, 4

+ Details

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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
-Topic 420
-SubTopic 10
-Section 40
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6394291&loc=d3e17658-110867

Reference 2: 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))
-URI http://asc.fasb.org/extlink&oid=27011515&loc=d3e140904-122747

Reference 3: 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 4: http://www.xbrl.org/2003/role/presentationRef
-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

No definition available.

+ Details

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