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Business Segments (Narrative) (Details) | 3 Months Ended
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Mar. 31, 2015
Business Segments [Abstract] |
Capital Charges Rate | 1.00%fstr_CapitalChargesRate
Segment Reporting, Measurement for Transactions Between Reportable Segments | Segment profits from 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 operations from December 31, 2014. The internal cost of capital charges are eliminated during the consolidation process.

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- Definition The internal cost of capital rate charged to a segment for assets used by the segment. + References No definition available. + Details
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- Definition A description of the basis of accounting for transactions between reportable segments. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 280 -SubTopic 10 -Section 50 -Paragraph 29 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=6534315&loc=d3e8864-108599 + Details
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