Debt Instrument, Discount Percentage

No definition available.

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- Definition

Disposal Group, Including Discontinued Operation, Upfront Consideration

+ References

No definition available.

+ Details

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Period Type:	instant

- Definition

Amount of direct costs of the business combination including legal, accounting, and other costs incurred to consummate the business acquisition.

+ References

No definition available.

+ Details

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- Definition

Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 30
-Paragraph 7
-URI http://asc.fasb.org/extlink&oid=6911251&loc=d3e6578-128477

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-Section 50
-Paragraph 1
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-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 30
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=6911251&loc=d3e6613-128477

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- Definition

Amount of liabilities incurred by the acquirer as part of consideration transferred in a business combination.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 25
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=6911189&loc=d3e6405-128476

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-Publisher FASB
-Name Accounting Standards Codification
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-URI http://asc.fasb.org/extlink&oid=6911251&loc=d3e6578-128477

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 30
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=6911251&loc=d3e6613-128477

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Period Type:	duration

- Definition

The value of the financial instrument(s) that the original debt is being converted into in a noncash (or part noncash) transaction. "Part noncash" refers to that portion of the transaction not resulting in cash receipts or cash payments in the period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=98513485&loc=d3e4304-108586

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-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 50
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=98513485&loc=d3e4332-108586

+ Details

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

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

- Definition

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

+ 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))
-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 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(16))
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-Name Accounting Standards Codification
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+ Details

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

- 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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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 30
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-Paragraph 2
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+ 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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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Amount of consideration received or receivable for the disposal of assets and liabilities, including discontinued operation.

+ References

No definition available.

+ Details

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

- Definition

Amount of cash inflow from contractual arrangement with the lender, including but not limited to, letter of credit, standby letter of credit and revolving credit arrangements.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 14
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3255-108585

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-Name Accounting Standards Codification
-Topic 235
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-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(f))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The cash outflow during the period from the repayment of aggregate short-term and long-term debt. Excludes payment of capital lease obligations.

+ References

No definition available.

+ Details

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

- Definition

The cash outflow for debt initially having maturity due after one year or beyond the normal operating cycle, if longer.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 15
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3291-108585

+ Details

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Balance Type:	credit
Period Type:	duration

- Definition

Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event.

+ References

No definition available.

+ Details

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- Details

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Balance Type:
Period Type:

- Details

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Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

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Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

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Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentAxis=mnk_A2015RevolvingCreditFacilityMember
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Balance Type:
Period Type:

- Details

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- Details

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Balance Type:
Period Type:

- Details

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Balance Type:
Period Type:

- Details

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Period Type:

- Details

Name:	us-gaap_DebtInstrumentAxis=mnk_ReceivablesecuritizationMaturityDateofJuly2020Member
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- Details

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Subsequent Events (Details) - USD ($)	Feb. 27, 2018	Feb. 21, 2018	Feb. 13, 2018	Jan. 16, 2018	Jul. 28, 2017	Feb. 28, 2017	Jan. 08, 2018	Dec. 29, 2017	Dec. 30, 2016
Subsequent Event [Line Items]
Long-term Debt, Gross								$ 6,492,600,000	$ 5,965,800,000
Debt Conversion, Converted Instrument, Amount			$ 1,221
Hemostasis Products \| Subsequent Event [Member]
Subsequent Event [Line Items]
Consideration							$ 185,000,000
Disposal Group, Including Discontinued Operation, Upfront Consideration							$ 153,000,000
Sucampo [Member]
Subsequent Event [Line Items]
Business Acquisition, Transaction Costs								4,200,000
Sucampo [Member] \| Subsequent Event [Member]
Subsequent Event [Line Items]
Total consideration			1,200,000,000
Term Loan due 2025 [Member] \| Secured Debt \| Sucampo [Member] \| Subsequent Event [Member]
Subsequent Event [Line Items]
Long term debt			$ 600,000,000
Variable interest rate			30000.00%
Debt instrument, discount percentage			2500.00%
2015 Revolving Credit Facility \| Debentures
Subsequent Event [Line Items]
Long-term Debt, Gross								900,000,000	100,000,000
Sucampo 2021 Notes [Member] \| Convertible Debt Securities [Member] \| Subsequent Event [Member]
Subsequent Event [Line Items]
Long-term Debt, Gross			$ 300,000,000
Stated interest rate			3.25%
Debt Conversion, Converted Instrument, Amount	$ 73,500,000
Debt instrument, face amount			$ 1,000
Term Loan due Sept 2024 [Member]
Subsequent Event [Line Items]
Long-term Debt, Gross								1,851,200,000
Term Loan due Sept 2024 [Member] \| Subsequent Event [Member]
Subsequent Event [Line Items]
Repayments of Long-term Debt				$ 225,000,000
Term Loan due Sept 2024 [Member] \| Secured Debt
Subsequent Event [Line Items]
Long-term Debt, Gross								1,837,200,000	0
Receivable securitization, Maturity Date of July 2020 [Member] \| Subsequent Event [Member]
Subsequent Event [Line Items]
Long-term Debt, Gross		$ 225,000,000
Proceeds from Lines of Credit		25,000,000
Receivable securitization, Maturity Date of July 2020 [Member] \| Secured Debt
Subsequent Event [Line Items]
Variable interest rate					0.90%
Long-term Debt, Gross								200,000,000	$ 0
2017 Revolving Credit Facility [Member]
Subsequent Event [Line Items]
Long-term Debt, Gross		625,000,000
Repayments of Debt		$ 275,000,000
2017 Revolving Credit Facility [Member] \| Debentures
Subsequent Event [Line Items]
Variable interest rate						2.25%
Long-term Debt, Gross								$ 900,000,000