Schedule Of Reconciliation Of Changes In Projected Benefit Obligation, Fair Value Of Plan Assets And Funded Status Of Plan (Detail) - United Kingdom - USD ($) $ in Millions	12 Months Ended
Dec. 25, 2021	Dec. 26, 2020	Dec. 28, 2019
Defined Benefit Plan Disclosure [Line Items]
Obligation at beginning of period	$ 269	$ 236
Interest cost	4	5	$ 6
Plan settlements	(7)
Benefits paid	(5)	(8)
Actuarial (gain) loss	(1)	26
Currency translation	(3)	10
Obligation at end of period	257	269	236
Fair value of plan assets at beginning of period	360	312
Actual return on plan assets	12	41
Company contributions	2	2
Benefits paid	(4)	(8)
Currency translation	(5)	13
Fair value of plan assets at end of period	358	360	$ 312
Net amount recognized	$ 101	$ 91

Amount of increase (decrease) in plan assets of defined benefit plan from actual return (loss) determined by change in fair value of plan assets adjusted for contributions, benefit payments, and other expenses.

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Amount of gain (loss) from change in actuarial assumptions which (increases) decreases benefit obligation of defined benefit plan. Assumptions include, but are not limited to, interest, mortality, employee turnover, salary, and temporary deviation from substantive plan.

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Amount of actuarial present value of benefits attributed to service rendered by employee for defined benefit plan.

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Amount of payment to participant of defined benefit plan which decreases benefit obligation. For pension plan, payment includes, but is not limited to, pension benefits and death benefits. For other postretirement plan, payment includes, but is not limited to, prescription drug benefits, health care benefits, life insurance benefits, and legal, educational and advisory services.

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Amount of contribution received by defined benefit plan from employer which increases plan assets.

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Amount of asset segregated and restricted to provide benefit under defined benefit plan. Asset includes, but is not limited to, stock, bond, other investment, earning from investment, and contribution by employer and employee.

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Amount of foreign currency translation gain (loss) which (increases) decreases benefit obligation of defined benefit plan.

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Amount of funded (unfunded) status of defined benefit plan, measured as difference between fair value of plan assets and benefit obligation. Includes, but is not limited to, overfunded (underfunded) status.

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Amount of cost recognized for passage of time related to defined benefit plan.

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Amount of gain (loss) recognized in net periodic benefit (cost) credit from irrevocable action relieving primary responsibility for benefit obligation and eliminating risk related to obligation and assets used to effect settlement.

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