Fair Value Measurements (Details) - USD ($) $ in Millions	Sep. 30, 2021	Dec. 31, 2020
Assets:
Investments	$ 12	$ 11
Foreign Exchange Contracts	23	1
Total Assets at Fair Value	35	12
Liabilities:
Foreign Exchange Contracts	3	34
Total Liabilities at Fair Value	3	34
Supplemental Fair Value Information
Notes Payable and Overdrafts	497	406
Carrying amount — liability	7,546	5,334
Fixed Rate Debt, Excluding Capital Leases
Supplemental Fair Value Information
Notes Payable and Overdrafts	235	227
Carrying amount — liability	6,077	4,094
Fair value — liability	6,449	4,283
Variable Rate Debt, Excluding Capital Leases
Supplemental Fair Value Information
Notes Payable and Overdrafts	262	179
Carrying amount — liability	1,469	1,240
Fair value — liability	1,465	1,197
Quoted Prices in Active Markets for Identical Assets/Liabilities (Level 1)
Assets:
Investments	12	11
Foreign Exchange Contracts	0	0
Total Assets at Fair Value	12	11
Liabilities:
Foreign Exchange Contracts	0	0
Total Liabilities at Fair Value	0	0
Supplemental Fair Value Information
Fair value — liability	6,600	4,391
Significant Other Observable Inputs (Level 2)
Assets:
Investments	0	0
Foreign Exchange Contracts	23	1
Total Assets at Fair Value	23	1
Liabilities:
Foreign Exchange Contracts	3	34
Total Liabilities at Fair Value	3	34
Significant Unobservable Inputs (Level 3)
Assets:
Investments	0	0
Foreign Exchange Contracts	0	0
Total Assets at Fair Value	0	0
Liabilities:
Foreign Exchange Contracts	0	0
Total Liabilities at Fair Value	$ 0	$ 0