Guarantees (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
Sep. 26, 2014	Sep. 27, 2013
Others
Guarantor Obligations [Line Items]
Maximum future payments	$ 36.2
Maryland Heights, Missouri \| Surety Bond
Guarantor Obligations [Line Items]
Maximum future payments	57.2
Saint Louis, Missouri \| Letter of Credit
Guarantor Obligations [Line Items]
Maximum future payments	21.1
Mallinckrodt Baker \| Indemnification Agreement
Guarantor Obligations [Line Items]
Guarantor obligations, obligation term	17 years
Maximum future payments	71.4
Escrow	30.0
Mallinckrodt Baker \| Indemnification Agreement \| Other Liabilities
Guarantor Obligations [Line Items]
Guarantors obligation	16.6	20.1
Mallinckrodt Baker \| Indemnification Agreement \| Other assets
Guarantor Obligations [Line Items]
Escrow	19.4	23.5
Mallinckrodt Baker \| Enviornmental, Health and Safety Matters \| Indemnification Agreement \| Other Liabilities
Guarantor Obligations [Line Items]
Guarantors obligation	$ 13.9	$ 17.2

Describe the approximate term of the guarantee or each group of similar guarantees.

No definition available.

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- Definition

The designation of funds furnished by a borrower to a lender to assure future payments of the borrower's real estate taxes and insurance obligations with respect to a mortgaged property. Escrow deposits may be made for a variety of other purposes such as earnest money and contingent payments. This element excludes replacement reserves which are an escrow separately provided for within the US GAAP taxonomy.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-03.10)

-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

The current carrying amount of the liability for the freestanding or embedded guarantor's obligations under the guarantee or each group of similar guarantees.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 460

-SubTopic 10

-Section 50

-Paragraph 4

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=6851643&loc=d3e12069-110248

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Details

Name:	us-gaap_GuaranteeObligationsLineItems
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Data Type:	xbrli:stringItemType
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Period Type:	duration

- Definition

Maximum potential amount of future payments (undiscounted) the guarantor could be required to make under the guarantee or each group of similar guarantees before reduction for potential recoveries under recourse or collateralization provisions.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 460

-SubTopic 10

-Section 50

-Paragraph 4

-Subparagraph (b)(1)

-URI http://asc.fasb.org/extlink&oid=6851643&loc=d3e12069-110248

+ Details

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Balance Type:	credit
Period Type:	instant

- Details

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- Details

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Namespace Prefix:
Data Type:	na
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- Details

Name:	us-gaap_StatementGeographicalAxis=mnk_MarylandHeightsMissouriMember
Namespace Prefix:
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- Details

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