Employee Benefits Employee Benefits - Multi-employer Pension Plan Exit Liability - Narrative (Details) - USD ($) $ in Millions	3 Months Ended			9 Months Ended
	Sep. 26, 2020	Jun. 27, 2020	Sep. 28, 2019	Sep. 26, 2020	Sep. 28, 2019
Multiemployer Plans [Line Items]
Settlement agreement payment	$ 7
Settlement Agreement Gain		$ 5
Multiemployer Pension plan withdrawal pre-tax charge			$ 132	$ (5)	$ 132
Annual Cash Obligation			$ 8
Cash obligation period			20 years