Related Party Transactions (Details) - USD ($) $ in Millions		3 Months Ended		9 Months Ended
		Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Significant transactions with related parties
Operating revenues and other income		$ 28	$ 32	$ 80	$ 89
Purchases		25	47	72	147
Operating expenses and selling, general and administrative expenses		18	21	53	53
Net interest (income) expense	[1]	$ (3)	$ (12)	$ (7)	$ (36)

[1] *We paid interest to, or received interest from, various affiliates. See Note 5—Investments, Loans and Long-Term Receivables, for additional