Share Plans (Schedule of Restricted Share Unit Activity) (Details) - Restricted Share Units - $ / shares	12 Months Ended
Dec. 31, 2021	Dec. 25, 2020	Dec. 27, 2019	Dec. 28, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted-average period to recognize unrecognized compensation cost, share options	1 year 1 month 6 days
Restricted Share Unit Activity [Roll Forward]
Beginning balance	490,671	1,419,020	1,685,101
Granted			755,180
Exercised	(186,930)	(647,167)	(713,274)
Expired/Forfeited	(60,844)	(281,182)	(307,987)
Ending balance	242,897	490,671	1,419,020
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract]
Weighted-average grant date fair value, restricted share units	$ 19.40	$ 20.96	$ 22.68	$ 29.54
Weighted-average grant date fair value, granted restricted share units			20.13
Weighted-average grant date fair value, vested restricted share units	23.43	24.23	35.29
Weighted-average grant date fair value, forfeited restricted share units	$ 19.58	$ 22.11	$ 24.81
Performance Shares Award, Performance Period	4 years

Performance Shares Award, Performance Period

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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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The number of equity-based payment instruments, excluding stock (or unit) options, that were forfeited during the reporting period.

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- Definition

Weighted average fair value as of the grant date of equity-based award plans other than stock (unit) option plans that were not exercised or put into effect as a result of the occurrence of a terminating event.

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The number of grants made 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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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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The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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No definition available.

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Per share or unit weighted-average fair value of nonvested award under share-based payment arrangement. Excludes share and unit options.

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The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

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The weighted average fair value as of grant date pertaining to an equity-based award plan other than a stock (or unit) option plan for which the grantee gained the right during the reporting period, by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash in accordance with the terms of the arrangement.

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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.

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