Debt (Schedule of Short-term Debt) (Details) - USD ($) $ in Millions		Jun. 30, 2019	Dec. 31, 2018
Short-Term Borrowings and Current Installments of Long-Term Debt - Third Party and Affiliates
Current installments of long-term debt		$ 26	$ 367
Short-term borrowings, including amounts due to affiliates	[1]	68	77
Total		$ 319	$ 561
Weighted average interest rate, short-term borrowings		2.90%	3.20%
Revolving Credit Facility [Member]
Short-Term Borrowings and Current Installments of Long-Term Debt - Third Party and Affiliates
Weighted average interest rate, short-term borrowings		1.30%	6.00%
Accounts Receivable Securitization Facility [Member]
Short-Term Borrowings and Current Installments of Long-Term Debt - Third Party and Affiliates
Borrowings outstanding	[2]	$ 77	$ 77
Weighted average interest rate, short-term borrowings		3.30%	3.10%
Revolving Credit Facility [Member]
Short-Term Borrowings and Current Installments of Long-Term Debt - Third Party and Affiliates
Borrowings outstanding	[3]	$ 148	$ 40

[1] The weighted average interest rate was 2.9% and 3.2% as of June 30, 2019 and December 31, 2018, respectively.

[2] The weighted average interest rate was 3.3% and 3.1% as of June 30, 2019 and December 31, 2018, respectively.

[3] The weighted average interest rate was 1.3% and 6.0% as of June 30, 2019 and December 31, 2018, respectively.