Supplemental Financial Statement Data - Consolidated Balance Sheet (Unaudited) (Details) - USD ($) $ in Millions	Sep. 26, 2020	Dec. 28, 2019
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Trade receivables	$ 1,414	$ 1,315
Allowance for doubtful accounts	(22)	(10)
Redundable income taxes	17	56
Other receivables	217	215
Accounts receivable, net	1,626	1,576
Raw materials and supplies	334	303
Finished goods and materials in process	929	923
Inventories	1,263	1,226
Property	9,100	9,051
Accumulated depreciation	(5,616)	(5,439)
Property, net	3,484	3,612
Pension	298	241
Deferred income taxes	219	231
Nonpension postretirement benefits	328	283
Other	507	384
Other assets	1,352	1,139
Accrued income taxes	29	42
Accrued salaries and wages	316	290
Other	780	577
Other current liabilities	1,125	909
Income taxes payable	54	81
Nonpension postretirement benefits	32	33
Other	434	429
Other liabilities	$ 520	$ 543