Employee Benefits Employee Benefits - Multi-employer Pension Plan Exit Liability - Narrative (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
	Sep. 28, 2019	Sep. 28, 2019	Sep. 29, 2018
Multiemployer Plans [Line Items]
Pre tax charge multi-employer pension plan withdrawal		$ 132	$ 0
Annual cash obligation	$ 8
Cash obligation period	20 years
Other liabilities | COGS
Multiemployer Plans [Line Items]
Pre tax charge multi-employer pension plan withdrawal	$ 132