Fair Value Measurements - Fair Value of Financial Instruments Recorded and Carried at Book Value (Details) - USD ($) $ in Millions		Sep. 30, 2016	Dec. 31, 2015
Reported Value Measurement
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Note receivable, noncurrent	[1]	$ 71	$ 71
Long-term Debt	[2]	13,563	13,567
Estimate of Fair Value Measurement
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Note receivable, noncurrent	[1]	71	71
Long-term Debt, Fair Value	[2]	$ 15,031	$ 13,891

[1] Included within Investments in and Loans to Unconsolidated Affiliates.

[2] Excludes commercial paper, capital leases, unamortized items and fair value hedge carrying value adjustments