Debt Instrument, Discount Percentage

No definition available.

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- Definition

Debt Instrument, Periodic Payment, Interest, Frequency

+ References

No definition available.

+ Details

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- Definition

Debt Instrument, Periodic Payment, Percentage of Principal

+ References

No definition available.

+ Details

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Period Type:	instant

- Definition

Debt Instrument, Repurchase Percentage

+ References

No definition available.

+ Details

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Period Type:	duration

- Definition

Line Of Credit Facility, Future Contingent Maximum Borrowing Capacity

+ References

No definition available.

+ Details

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Period Type:	instant

- Definition

Long-term Loans Payable, Periodic Amortization Payment, Percentage of Original Principal Amount

+ References

No definition available.

+ Details

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Period Type:	duration

- Definition

Variable Rate Receivable Securitization

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

+ Details

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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Face (par) amount of debt instrument at time of issuance.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 55
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=64930739&loc=d3e28878-108400

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-Name Accounting Standards Codification
-Topic 835
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-Section 45
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-URI http://asc.fasb.org/extlink&oid=64930785&loc=d3e28551-108399

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

+ Details

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Period Type:	instant

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Percentage price of original principal amount of debt at which debt can be redeemed by the issuer.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 470
-Section 50
-Paragraph 3
-Subparagraph e
-URI http://asc.fasb.org/extlink&oid=6479336&loc=d3e64711-112823

+ Details

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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount, after accumulated amortization, of debt discount.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 1A
-URI http://asc.fasb.org/extlink&oid=64930785&loc=d3e28541-108399

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+ Details

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

- Definition

The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

+ 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))
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+ Details

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Namespace Prefix:	us-gaap_
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Balance Type:	credit
Period Type:	instant

- Definition

The fee, expressed as a percentage of the line of credit facility, for the line of credit facility regardless of whether the facility has been used.

+ References

No definition available.

+ Details

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

- Definition

The effective interest rate at the end of the reporting period.

+ References

+ Details

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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

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

- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

+ Details

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

- Definition

Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
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-Section S99
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+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of expense related to credit loss from transactions other than loan and lease transactions.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 225
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04(11))
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+ Details

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Balance Type:	debit
Period Type:	duration

- Details

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- Details

Name:	us-gaap_DebtInstrumentAxis=mnk_A2015RevolvingCreditFacilityMember
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- Details

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- Details

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- Details

Name:	us-gaap_LongtermDebtTypeAxis=mnk_PriorToApril152018Member
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- Details

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- Details

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Balance Type:
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- Details

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- Details

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Debt (Narrative) (Details) - USD ($)				12 Months Ended
Debt (Narrative) (Details) - USD ($)	Sep. 24, 2015	Apr. 15, 2015	Mar. 19, 2014	Sep. 30, 2016	Sep. 25, 2015	Aug. 28, 2015	Jan. 20, 2015	Aug. 31, 2014	Aug. 14, 2014	Jul. 28, 2014	Apr. 30, 2013
Debt Instrument [Line Items]
Variable rate receivable securitization				$ 0	$ 153,000,000
Term loan due March 2021
Debt Instrument [Line Items]
Frequency of interest payment			90 days
Debt instrument, unamortized discount				$ 3,300,000
Quarterly amortization payments			0.00%
Debt instrument, discount percentage			0.25%
2015 Revolving Credit Facility
Debt Instrument [Line Items]
Line of Credit Facility, Interest Rate at Period End				3.10%
New Term Loan
Debt Instrument [Line Items]
Debt instrument, face amount								$ 700,000,000
2023 Notes
Debt Instrument [Line Items]
Debt Instrument, Redemption Price, Percentage	100.00%
Prior To April 15, 2018 \| 2025 Notes
Debt Instrument [Line Items]
Debt Instrument, Redemption Price, Percentage		40.00%
Revolving Credit Facility
Debt Instrument [Line Items]
Maximum borrowing capacity			$ 250,000,000
Revolving Credit Facility \| Term loan due March 2021
Debt Instrument [Line Items]
Provision for other credit losses			150,000,000
Facility fees for letters of credit				0.275%
2015 Replacement Revolving Credit Facility
Debt Instrument [Line Items]
Maximum borrowing capacity						$ 250,000,000
2015 Incremental Revolving Credit Facility
Debt Instrument [Line Items]
Maximum borrowing capacity						250,000,000
2015 Revolving Credit Facility
Debt Instrument [Line Items]
Maximum borrowing capacity						$ 500,000,000
Debentures \| 2020 Notes
Debt Instrument [Line Items]
Debt instrument, face amount		$ 700,000,000
Stated interest rate		4.875%
Debentures \| 2023 Notes
Debt Instrument [Line Items]
Debt instrument, face amount	$ 750,000,000
Stated interest rate	5.625%
Debentures \| 2025 Notes
Debt Instrument [Line Items]
Debt instrument, face amount		$ 700,000,000
Stated interest rate		5.50%
Prior To April 15, 2017 \| 2023 Notes
Debt Instrument [Line Items]
Debt Instrument, Redemption Price, Percentage	40.00%
Line of Credit
Debt Instrument [Line Items]
Borrowings, outstanding					$ 0
Senior Notes \| 3.50% notes due April 2018
Debt Instrument [Line Items]
Debt instrument, face amount											$ 300,000,000
Stated interest rate											3.50%
Senior Notes \| 4.75% notes due April 2023
Debt Instrument [Line Items]
Debt instrument, face amount											$ 600,000,000
Stated interest rate											4.75%
Senior Notes \| 5.75% notes due August 2022
Debt Instrument [Line Items]
Debt instrument, face amount								$ 900,000,000
Stated interest rate								5.75%
Secured Debt \| Term loan due March 2021
Debt Instrument [Line Items]
Debt instrument, face amount			$ 1,300,000,000
Interest rate during period				3.43%
Secured Debt \| Variable rate receivable securitization
Debt Instrument [Line Items]
Debt instrument, face amount										$ 160,000,000
Maximum borrowing capacity							$ 250,000,000			160,000,000
Line Of Credit Facility, Future Contingent Maximum Borrowing Capacity										$ 300,000,000
Facility fees for letters of credit					0.35%
Variable interest rate					0.80%
Interest rate during period				1.33%
Variable rate receivable securitization				$ 235,000,000
Secured Debt \| New Term Loan
Debt Instrument [Line Items]
Debt Instrument, Periodic Payment, Percentage of Principal									0.25%
Secured Debt \| Term Loan and New Term Loan
Debt Instrument [Line Items]
Long-term Debt				$ 1,953,500,000
Prior to August 1, 2017 \| 5.75% notes due August 2022
Debt Instrument [Line Items]
Debt Instrument, Redemption Price, Percentage					40.00%
Option A \| 5.75% notes due August 2022
Debt Instrument [Line Items]
Repurchase percentage					101.00%
Option A \| 2023 Notes
Debt Instrument [Line Items]
Repurchase percentage	101.00%
Option A \| 2025 Notes
Debt Instrument [Line Items]
Repurchase percentage		101.00%
Option B \| 5.75% notes due August 2022
Debt Instrument [Line Items]
Repurchase percentage					100.00%
Option B \| 2023 Notes
Debt Instrument [Line Items]
Repurchase percentage	100.00%
Option B \| 2025 Notes
Debt Instrument [Line Items]
Repurchase percentage		100.00%
LIBOR \| Term loan due March 2021
Debt Instrument [Line Items]
Stated interest rate			0.75%
Letter of Credit \| Revolving Credit Facility
Debt Instrument [Line Items]
Borrowings, outstanding					$ 0