Retirement Plans - Fair Value of Pension Plan Assets (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2022	Jan. 01, 2022	Jan. 02, 2021
Change in fair value of plan assets
Valuation of owned properties period	3 years
Pension Benefits
Change in fair value of plan assets
Fair value of total pension plan assets	$ 7,943	$ 9,947	$ 9,080
Level 1 | Pension Benefits
Change in fair value of plan assets
Fair value of total pension plan assets	4,393	5,696
Level 2 | Pension Benefits
Change in fair value of plan assets
Fair value of total pension plan assets	905	1,335
Level 3 | Pension Benefits
Change in fair value of plan assets
Fair value of total pension plan assets	569	599
Not Subject to Leveling | Pension Benefits
Change in fair value of plan assets
Fair value of total pension plan assets	2,076	2,317
Cash and equivalents | Level 1 | Pension Benefits
Change in fair value of plan assets
Fair value of total pension plan assets	378	200
Cash and equivalents | Level 2 | Pension Benefits
Change in fair value of plan assets
Fair value of total pension plan assets	3	6
Cash and equivalents | Level 3 | Pension Benefits
Change in fair value of plan assets
Fair value of total pension plan assets	0	0
Cash and equivalents | Not Subject to Leveling | Pension Benefits
Change in fair value of plan assets
Fair value of total pension plan assets	0	0
Domestic equity securities | Level 1 | Pension Benefits
Change in fair value of plan assets
Fair value of total pension plan assets	2,304	2,774
Domestic equity securities | Level 2 | Pension Benefits
Change in fair value of plan assets
Fair value of total pension plan assets	0	0
Domestic equity securities | Level 3 | Pension Benefits
Change in fair value of plan assets
Fair value of total pension plan assets	0	0
Domestic equity securities | Not Subject to Leveling | Pension Benefits
Change in fair value of plan assets
Fair value of total pension plan assets	225	271
International equity securities | Level 1 | Pension Benefits
Change in fair value of plan assets
Fair value of total pension plan assets	1,171	1,772
International equity securities | Level 2 | Pension Benefits
Change in fair value of plan assets
Fair value of total pension plan assets	0	0
International equity securities | Level 3 | Pension Benefits
Change in fair value of plan assets
Fair value of total pension plan assets	0	0
International equity securities | Not Subject to Leveling | Pension Benefits
Change in fair value of plan assets
Fair value of total pension plan assets	230	305
Mutual funds | Level 1 | Pension Benefits
Change in fair value of plan assets
Fair value of total pension plan assets	150	123
Mutual funds | Level 2 | Pension Benefits
Change in fair value of plan assets
Fair value of total pension plan assets	0	0
Mutual funds | Level 3 | Pension Benefits
Change in fair value of plan assets
Fair value of total pension plan assets	0	0
National, state and local governments | Level 1 | Pension Benefits
Change in fair value of plan assets
Fair value of total pension plan assets	332	677
National, state and local governments | Level 2 | Pension Benefits
Change in fair value of plan assets
Fair value of total pension plan assets	239	274
National, state and local governments | Level 3 | Pension Benefits
Change in fair value of plan assets
Fair value of total pension plan assets	0	0
National, state and local governments | Not Subject to Leveling | Pension Benefits
Change in fair value of plan assets
Fair value of total pension plan assets	27	98
Corporate debt | Level 1 | Pension Benefits
Change in fair value of plan assets
Fair value of total pension plan assets	58	150
Corporate debt | Level 2 | Pension Benefits
Change in fair value of plan assets
Fair value of total pension plan assets	663	1,055
Corporate debt | Level 3 | Pension Benefits
Change in fair value of plan assets
Fair value of total pension plan assets	0	0
Corporate debt | Not Subject to Leveling | Pension Benefits
Change in fair value of plan assets
Fair value of total pension plan assets	129	170
Private investment partnerships | Level 1 | Pension Benefits
Change in fair value of plan assets
Fair value of total pension plan assets	0	0
Private investment partnerships | Level 2 | Pension Benefits
Change in fair value of plan assets
Fair value of total pension plan assets	0	0
Private investment partnerships | Level 3 | Pension Benefits
Change in fair value of plan assets
Fair value of total pension plan assets	0	0
Private investment partnerships | Not Subject to Leveling | Pension Benefits
Change in fair value of plan assets
Fair value of total pension plan assets	1,070	1,098
Real estate | Level 1 | Pension Benefits
Change in fair value of plan assets
Fair value of total pension plan assets	0	0
Real estate | Level 2 | Pension Benefits
Change in fair value of plan assets
Fair value of total pension plan assets	0	0
Real estate | Level 3
Change in fair value of plan assets
Fair value of total pension plan assets	569	599	$ 458
Real estate | Level 3 | Pension Benefits
Change in fair value of plan assets
Fair value of total pension plan assets	569	599
Real estate | Not Subject to Leveling | Pension Benefits
Change in fair value of plan assets
Fair value of total pension plan assets	$ 395	$ 375