Acquisitions and Divestitures Investment Divestiture (Details) - USD ($) $ in Millions |
12 Months Ended | |||
---|---|---|---|---|
Dec. 31, 2015 |
Dec. 31, 2014 |
Dec. 31, 2013 |
Mar. 14, 2013 |
|
Business Acquisition [Line Items] | ||||
Proceeds from sales of assets and investments | $ 0 | $ 0 | $ 490 | |
Income Tax Expense | (564) | (648) | (742) | |
Equity Method Investments | $ 6,032 | $ 6,028 | ||
Express Pipeline System and Subordinated Debenture Investments [Member] | Spectra Energy Corp. [Member] | ||||
Business Acquisition [Line Items] | ||||
Proceeds from sales of assets and investments | 402 | |||
Equity Method Investment, Realized Gain (Loss) on Disposal | 224 | |||
Income Tax Expense | $ (84) | |||
Kinder Morgan Energy Partners, L.P. [Member] | Express Pipeline System [Member] | ||||
Business Acquisition [Line Items] | ||||
Equity Method Investment, Ownership Percentage | 33.33% |