Dispositions Dispositions (Details) - USD ($) $ in Millions			3 Months Ended
	Jan. 27, 2016	Jan. 01, 2016	Mar. 31, 2016	Mar. 31, 2015
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Proceeds from the sale of businesses, net of cash sold			$ 115	$ 0
Gain (Loss) on Disposition of Business			47	1
Proceeds from sale of ownership interest			$ (134)	$ (247)
DPLER [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Proceeds from the sale of businesses, net of cash sold		$ 76
Gain (Loss) on Disposition of Business		$ 49
Kelanitissa [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Proceeds from the sale of businesses, net of cash sold	$ 18
Gain (Loss) on Disposition of Business	$ (5)