Business Segments (Narrative) (Details)	3 Months Ended
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.

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

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

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