Cash Payments For Interest (Net of Amounts Capitalized) (Details 5) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Debt Disclosure [Abstract]
Cash payments for interest (net of amounts capitalized)	$ 681us-gaap_InterestPaidNet	$ 472us-gaap_InterestPaidNet	$ 479us-gaap_InterestPaidNet

The amount of cash paid for interest during the period net of cash paid for interest that is capitalized.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 50

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6367179&loc=d3e4297-108586

Name:	us-gaap_InterestPaidNet
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration