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Share-Based Compensation (Narrative) (Details)	9 Months Ended
	Sep. 30, 2015 shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Performance period of restricted stock units (in years)	3 years
Target Restricted Stock Units, 2015 Grants [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Nonvested Options Forfeited, Number of Shares	1,000
Target Restricted Stock Units, 2014 Grants [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Nonvested Options Forfeited, Number of Shares	8,000
Target Restricted Stock Units, 2013 Grants [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Nonvested Options Forfeited, Number of Shares	6,000
Options granted prior to 2008 [Member] | Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Option vesting term (in years)	4 years
Options granted prior to 2008 [Member] | Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Option vesting term (in years)	5 years
Options granted subsequent to January 1, 2008 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Option vesting term (in years)	4 years

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+ References

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- Definition

Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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



-Publisher FASB



-Name Accounting Standards Codification



-Topic 718



-SubTopic 10



-Section 50



-Paragraph 2



-Subparagraph (a)(1)



-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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