[Line Items] for Business Acquisition, Pro Forma Information

No definition available.

Name:	mnk_BusinessAcquisitionProFormaInformationLineItems
Namespace Prefix:	mnk_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Per basic share amount of pro forma income from continuing operations, after tax, as if the business combination had been completed at the beginning of a period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (h)(2)-(3)
-URI http://asc.fasb.org/extlink&oid=65885119&loc=d3e1392-128463

+ Details

Name:	us-gaap_BusinessAcquisitionProFormaIncomeLossFromContinuingOperationsBeforeChangesInAccountingAndExtraordinaryItemsNetOfTaxPerShareBasic
Namespace Prefix:	us-gaap_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	duration

- Definition

Per diluted share amount of pro forma income from continuing operations, after tax, as if the business combination had been completed at the beginning of a period.

+ References

+ Details

Name:	us-gaap_BusinessAcquisitionProFormaIncomeLossFromContinuingOperationsBeforeChangesInAccountingAndExtraordinaryItemsNetOfTaxPerShareDiluted
Namespace Prefix:	us-gaap_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount after tax of pro forma income from continuing operations as if the business combination had been completed at the beginning of a period.

+ References

+ Details

Name:	us-gaap_BusinessAcquisitionsProFormaIncomeLossFromContinuingOperationsBeforeChangesInAccountingAndExtraordinaryItemsNetOfTax
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

The pro forma revenue for a period as if the business combination or combinations had been completed at the beginning of the period.

+ References

+ Details

Name:	us-gaap_BusinessAcquisitionsProFormaRevenue
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22(a)(1))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=64930785&loc=d3e28551-108399

+ Details

Name:	us-gaap_DebtInstrumentInterestRateEffectivePercentage
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

The effective interest rate during the reporting period.

+ References

+ Details

Name:	us-gaap_LineOfCreditFacilityInterestRateDuringPeriod
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Details

Name:	us-gaap_DebtInstrumentAxis=mnk_A2023NotesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_BusinessAcquisitionAxis=mnk_TherakosMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentAxis=mnk_A2020NotesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_BusinessAcquisitionAxis=mnk_IkariaMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentAxis=mnk_A2025NotesMemberMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentAxis=mnk_A2015RevolvingCreditFacilityMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Acquisitions and License Agreements (Schedule of Unaudited Pro Forma Information) (Details) - USD ($) $ / shares in Units, $ in Millions		3 Months Ended		9 Months Ended
	Sep. 25, 2015	Jun. 24, 2016	Jun. 26, 2015	Jun. 24, 2016	Jun. 26, 2015	Apr. 16, 2015
Business Acquisition, Pro Forma Information [Line Items]
Net sales, pro forma		$ 970.6	$ 940.4	$ 2,803.4	$ 2,827.3
Pro forma, income from continuing operations		$ 195.7	$ 76.2	$ 442.2	$ 256.9
Pro forma, basic earnings per share from continuing operations		$ 1.80	$ 0.66	$ 3.96	$ 2.22
Pro forma, diluted earnings per shares from continuing operations		$ 1.79	$ 0.65	$ 3.93	$ 2.19
2023 Notes [Member] \| Therakos
Business Acquisition, Pro Forma Information [Line Items]
Interest rate	5.625%
2020 Notes \| Ikaria, Inc.
Business Acquisition, Pro Forma Information [Line Items]
Interest rate						4.875%
2025 Notes \| Ikaria, Inc.
Business Acquisition, Pro Forma Information [Line Items]
Interest rate						5.50%
2015 Revolving Credit Facility
Business Acquisition, Pro Forma Information [Line Items]
Line of Credit Facility, Interest Rate on date of acquisition	2.58%