Business Segments (Narrative) (Details)	9 Months Ended
Sep. 30, 2012
Business Segments [Abstract]
Capital Charges Rate	1.00%
Segment Reporting, Measurement for Transactions Between Reportable Segments	Segment profits from continuing operations, as shown above, include internal cost of capital charges for assets used in the segment at a rate of, generally, 1% per month. There has been no change in the measurement of segment profit from continuing operations from December 31, 2011.

A description of the basis of accounting for transactions between reportable segments.

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 131

-Paragraph 31

-Subparagraph a

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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

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