Income Taxes Income Taxes (Taxes on Foreign Earnings) (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2016	Jun. 30, 2016
Unremitted Earnings [Member] \| International Energy [Member]
Income Tax Disclosure [Line Items]
U.S. Income Taxes on Foreign Earnings	$ 4	$ 16
Previously Remitted Earnings [Member]
Income Tax Disclosure [Line Items]
U.S. Income Taxes on Foreign Earnings		$ (95)

Amount of current and deferred foreign income tax expense (benefit) attributable to income (loss) from continuing operations.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(h)(1))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

Name:	us-gaap_ForeignIncomeTaxExpenseBenefitContinuingOperations
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration