Derivatives and Hedge Accounting Activities (Narrative) (Details) (USD $) In Millions	3 Months Ended	6 Months Ended
Jun. 30, 2010	Jun. 30, 2010
Derivatives and Hedge Accounting Activities
Reclassification of gains from AOCI to earnings	$ 70	$ 110
Reclassification of gains from AOCI to earnings, after-tax	43	67
Fair value of AOCI earnings, partially offset by subsequent changes	37	37
Fair value of AOCI earnings, partially offset by subsequent changes, after-tax	$ 23	$ 23

The amount of net gains or losses on a cash flow hedge reclassified in the period to earnings from accumulated other comprehensive income.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 133
-Paragraph 45
-Subparagraph b(1)
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4C
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=6935481&loc=SL5624171-113959

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=6887037&loc=d3e80784-113994

Name:	us-gaap_CashFlowHedgeGainLossReclassifiedToEarningsNet
Namespace Prefix:	us-gaap
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration