Restructuring Program - Narrative (Details) - USD ($) $ in Millions				3 Months Ended		95 Months Ended
	Sep. 06, 2018	Aug. 31, 2016	May 06, 2014	Mar. 31, 2022	Mar. 31, 2021	Mar. 31, 2022	Dec. 31, 2021
2014-2018 Restructuring Program
Restructuring Cost and Reserve [Line Items]
Approved restructuring program cost		$ 5,700	$ 3,500
Reallocation of previously approved capital expenditures to be spent on restructuring program cash costs		600
2014-2018 Restructuring Program | Maximum
Restructuring Cost and Reserve [Line Items]
Approved capital expenditures		1,600	$ 2,200
2014-2018 Restructuring Program | Restructuring Program Charges
Restructuring Cost and Reserve [Line Items]
Approved restructuring program cost		4,100
2014-2018 Restructuring Program | Cash Costs
Restructuring Cost and Reserve [Line Items]
Approved restructuring program cost		3,100
2014-2018 Restructuring Program | Non-cash Costs
Restructuring Cost and Reserve [Line Items]
Approved restructuring program cost		$ 1,000
Simplify to Grow Program
Restructuring Cost and Reserve [Line Items]
Approved restructuring program cost	$ 7,700
Restructuring and implementation charges				$ 31	$ 122	$ 5,055
Restructuring charges				11	88	3,047
Cash spent in restructuring				17
Non-cash asset write-downs				2
Gain on sale of property					40
Restructuring reserve				202		202	$ 211
Implementation costs				20	34	2,008
Simplify to Grow Program | Maximum
Restructuring Cost and Reserve [Line Items]
Approved capital expenditures	2,300
Increase in approved restructuring program costs	1,300
Increase in approved capital expenditures	700
Simplify to Grow Program | Other current liabilities
Restructuring Cost and Reserve [Line Items]
Restructuring reserve				172		172
Simplify to Grow Program | Other liabilities
Restructuring Cost and Reserve [Line Items]
Restructuring reserve				30		30
Simplify to Grow Program | Restructuring Program Charges
Restructuring Cost and Reserve [Line Items]
Approved restructuring program cost	5,400
Simplify to Grow Program | Cash Costs
Restructuring Cost and Reserve [Line Items]
Approved restructuring program cost	4,100
Simplify to Grow Program | Non-cash Costs
Restructuring Cost and Reserve [Line Items]
Approved restructuring program cost	$ 1,300
Simplify to Grow Program | Severance and Related Costs
Restructuring Cost and Reserve [Line Items]
Restructuring charges				9
Cash spent in restructuring				17	$ 34
Non-cash asset write-downs				0
Restructuring reserve				$ 202		$ 202	$ 211