Performance Shares Award, Performance Period

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- Definition

Performance Shares, Percentage of Ordinary Shares Awarded

+ References

No definition available.

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- Definition

Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
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- Definition

Amount of deferred tax expense from write-off of the deferred tax asset related to deductible stock options at exercise.

+ References

No definition available.

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- Definition

Maximum amount the employee may contribute to a defined contribution plan.

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- Definition

Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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- Definition

Amount of cost to be recognized for nonvested award under share-based payment arrangement. Excludes share and unit options.

+ References

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- Definition

Amount of cost to be recognized for option under share-based payment arrangement.

+ References

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- Definition

Amount of tax benefit for recognition of expense of award under share-based payment arrangement.

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- Definition

Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

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- Definition

Discount rate from fair value on purchase date that participants pay for shares.

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- Definition

The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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- Definition

Fair value of share-based awards for which the grantee gained the right by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash.

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- 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.

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- Definition

Number of shares authorized for issuance under share-based payment arrangement.

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- Definition

Amount by which current fair value of underlying stock exceeds exercise price of fully vested and expected to vest exercisable or convertible options. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

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- Definition

Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Share Plans (Narrative) (Details) - USD ($)	12 Months Ended
Share Plans (Narrative) (Details) - USD ($)	Dec. 31, 2021	Dec. 25, 2020	Dec. 27, 2019	May 16, 2018	Mar. 19, 2015	Jul. 01, 2013
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation cost	$ 10,200,000	$ 25,300,000	$ 33,800,000
Tax benefit from share-based compensation cost	$ 0	$ 0	1,200,000
Intrinsic value of options vested			300,000
Tax benefit from stock options exercised			$ 100,000
Share Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award Vesting Period	4 years
Expiration period	10 years
Unrecognized compensation cost, share options	$ 1,600,000
Weighted-average period to recognize unrecognized compensation cost, share options	1 year
Restricted Share Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted-average grant date fair value, granted restricted share units			$ 20.13
Weighted-average period to recognize unrecognized compensation cost, share options	1 year 1 month 6 days
Fair value of restricted share units vested in period	$ 4,400,000
Unrecognized compensation cost, restricted share units	$ 1,900,000
Performance Shares Award, Performance Period	4 years
Employee Stock Purchase Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Discount from Market Price, Purchase Date	15.00%
Performance Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted-average grant date fair value, granted restricted share units			$ 32.46
2013 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares authorized under 2013 Plan						5,700,000
2015 Mallinckrodt Pharmaceuticals Stock and Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares authorized under 2013 Plan					17,800,000
2018 Mallinckrodt Pharmaceuticals Stock and Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares authorized under 2013 Plan				26,800,000
Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of ordinary shares to be awarded	0.00%
Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of ordinary shares to be awarded	200.00%
New ESPP [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Defined Contribution Plan, Maximum Annual Contributions Per Employee, Amount	$ 25,000