Retirement Benefits and Trusteed Assets (Details Textuals) (USD $) In Millions	1 Months Ended	9 Months Ended
Jan. 31, 2011	Sep. 30, 2011	Dec. 31, 2011 Other Postretirement Benefit Plans, Defined Benefit [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Defined Benefit Plan, Contributions by Employer		$ 200
Other Postretirement Benefits Payments	81
Defined Benefit Plan, Estimated Future Employer Contributions in Current Fiscal Year			$ 125

The amount of cash or cash equivalents contributed during the reporting period by the entity to fund non-pension postretirement benefits.

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 95

-Paragraph 28

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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 230

-SubTopic 10

-Section 45

-Paragraph 25

-Subparagraph (g)

-URI http://asc.fasb.org/extlink&oid=6943989&loc=d3e3536-108585

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