Fair Value Measurements (Details) - USD ($) $ in Millions	Sep. 30, 2020	Dec. 31, 2019
Assets:
Investments	$ 10	$ 11
Foreign Exchange Contracts	21	11
Total Assets at Fair Value	31	22
Liabilities:
Foreign Exchange Contracts	15	19
Total Liabilities at Fair Value	15	19
Supplemental Fair Value Information
Carrying amount — liability	5,871	5,066
Notes Payable and Overdrafts	529	348
Fixed Rate Debt, Excluding Capital Leases
Supplemental Fair Value Information
Carrying amount — liability	4,059	3,434
Fair value — liability	4,054	3,558
Notes Payable and Overdrafts	268	143
Variable Rate Debt, Excluding Capital Leases
Supplemental Fair Value Information
Carrying amount — liability	1,812	1,632
Fair value — liability	1,725	1,632
Notes Payable and Overdrafts	261	205
Quoted Prices in Active Markets for Identical Assets/Liabilities (Level 1)
Assets:
Investments	10	11
Foreign Exchange Contracts	0	0
Total Assets at Fair Value	10	11
Liabilities:
Foreign Exchange Contracts	0	0
Total Liabilities at Fair Value	0	0
Supplemental Fair Value Information
Fair value — liability	4,191	3,808
Significant Other Observable Inputs (Level 2)
Assets:
Investments	0	0
Foreign Exchange Contracts	21	11
Total Assets at Fair Value	21	11
Liabilities:
Foreign Exchange Contracts	15	19
Total Liabilities at Fair Value	15	19
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