Restructuring Charges - Schedule of Balance of Restructuring Activities (Details) - USD ($) $ in Millions	6 Months Ended	12 Months Ended
Jun. 26, 2021	Jun. 27, 2020	Dec. 26, 2020	Dec. 28, 2019	Dec. 29, 2018
Restructuring Cost And Reserve [Line Items]
Additional accruals	$ 8	$ 1	$ 2	$ 6	$ 19
Employee Severance and Benefits
Restructuring Cost And Reserve [Line Items]
Restructuring Reserve	16	$ 2	2	1	4
Additional accruals	32		25	20	27
Cash payments	(41)		(11)	(19)	(30)
Restructuring Reserve	$ 7		$ 16	2	1
Facility Restructuring
Restructuring Cost And Reserve [Line Items]
Restructuring Reserve				4	7
Additional accruals					2
Cash payments					(5)
Adjustment				$ (4)
Restructuring Reserve					$ 4

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.

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Amount of expenses associated with exit or disposal activities pursuant to an authorized plan. Excludes expenses related to a discontinued operation or an asset retirement obligation.

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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.

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Amount of increase (decrease) in the accrual for restructuring costs.

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