Income Taxes - Summary of Tax Attribute Carryforwards (Details) $ in Millions	Dec. 26, 2020 USD ($)
Federal
Tax Attribute Carryforwards [Line Items]
Operating loss carryforwards, amount	$ 5,200
Tax credit carryforward, amount	385
State/Provincial
Tax Attribute Carryforwards [Line Items]
Operating loss carryforwards, amount	343
Tax credit carryforward, amount	252
Canada Tax Authority
Tax Attribute Carryforwards [Line Items]
Tax credit carryforward, amount	$ 494