Debt (Schedule of Short-term Debt) (Details) - USD ($) $ in Millions		Dec. 31, 2017		Dec. 31, 2016
Short-Term Borrowings and Current Installments of Long-Term Debt - Third Party and Affiliates
Current installments of long-term debt		$ 63		$ 27
Short-term borrowings, including amounts due to affiliates	[1]	86		68
Total		$ 326		$ 118
Weighted average interest rate, short-term borrowings		2.80%		3.10%
Bank Loans Acquired from SOFTER [Member]
Short-Term Borrowings and Current Installments of Long-Term Debt - Third Party and Affiliates
Short-term SOFTER bank loans (Note 4)	[2]	$ 0		$ 23
Weighted average interest rate, short-term borrowings				1.20%
Revolving Credit Facility [Member]
Short-Term Borrowings and Current Installments of Long-Term Debt - Third Party and Affiliates
Line of Credit, Current	[4]	$ 97	[3]	$ 0
Weighted average interest rate, short-term borrowings		4.10%
Accounts Receivable Securitization Facility [Member]
Short-Term Borrowings and Current Installments of Long-Term Debt - Third Party and Affiliates
Line of Credit, Current	[6]	$ 80	[5]	$ 0
Weighted average interest rate, short-term borrowings		2.10%

[1] The weighted average interest rate was 2.8% and 3.1% as of December 31, 2017 and 2016, respectively.

[2] The weighted average interest rate was 1.2% as of December 31, 2016.

[3] The Company borrowed $528 million and repaid $431 million under its senior unsecured revolving credit facility during the year ended December 31, 2017

[4] The weighted average interest rate was 4.1% as of December 31, 2017.

[5] The Company borrowed $85 million and repaid $5 million during the year ended December 31, 2017.

[6] The weighted average interest rate was 2.1% as of December 31, 2017.