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Summary of Significant Accounting Policies Awards Outstanding (Details) - shares	Jun. 30, 2015	Dec. 31, 2014
Stock options
Awards outstanding [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number	867,877	961,377
Restricted Stock Units (RSUs) [Member]
Awards outstanding [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Outstanding, Number	2,103,751	1,830,291
Performance Shares [Member]
Awards outstanding [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Outstanding, Number	32,000	34,000
Stock appreciation rights
Awards outstanding [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Outstanding, Number	605,692	673,068
Market share units
Awards outstanding [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Outstanding, Number	563,300	444,272

X

- Definition

Awards outstanding [Line Items]

+ References

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- Definition

Number of equity instruments other than options outstanding, including both vested and non-vested instruments.

+ 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 (c)(1)(i)



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



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Number of options outstanding, including both vested and non-vested options.

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-Name Accounting Standards Codification



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