Cash Restructuring Charges

No definition available.

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Namespace Prefix:	mnk_
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Balance Type:	debit
Period Type:	duration

- Definition

Total restructuring and related expense

+ References

No definition available.

+ Details

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

- 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/disclosureRef
-Topic 420
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (b)(2)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482017/420-10-50-1

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 230
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 17
-Subparagraph (f)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482740/230-10-45-17

+ Details

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

- 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/disclosureRef
-Topic 420
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 2
-Subparagraph (SAB Topic 5.P.4.b.2)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479823/420-10-S99-2

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 420
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (b)(2)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482017/420-10-50-1

+ Details

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

- Definition

Amount of expense (reversal of expense) which increases (decreases) the restructuring reserve from an adjustment to a previously accrued restructuring liability.

+ References

+ Details

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

- 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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- Details

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- Details

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- Details

Name:	us-gaap_RestructuringCostAndReserveAxis=us-gaap_ContractTerminationMember
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Restructuring and Related Charges (Schedule of Restructuring Reserves by Type of Cost) (Details) - Restructuring Fiscal 2021 Plan - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 27, 2025	Jun. 28, 2024	Jun. 27, 2025	Jun. 28, 2024
Restructuring Reserve [Roll Forward]
Beginning Balance			$ 1.3
Charges from continuing operations			0.1
Cash (payments)/receipts			0.9
Ending Balance	$ 0.0		0.0
Total Restructuring And Related Expense	(0.2)	$ 0.2	(2.2)	$ 10.4
Restructuring Reserve, Accrual Adjustment			(2.3)
One-time Termination Benefits
Restructuring Reserve [Roll Forward]
Beginning Balance			0.2
Charges from continuing operations			0.0
Cash (payments)/receipts			0.2
Ending Balance	0.0		0.0
Restructuring Reserve, Accrual Adjustment			0.0
Contract Termination
Restructuring Reserve [Roll Forward]
Beginning Balance			1.1
Charges from continuing operations			0.1
Cash (payments)/receipts			1.1
Ending Balance	$ 0.0		0.0
Restructuring Reserve, Accrual Adjustment			$ (2.3)