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Summary of Significant Accounting Policies Awards Outstanding (Details) | Mar. 31, 2014 | Dec. 31, 2013
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Stock options |  |
Awards outstanding [Line Items] |  |
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number | 993,677 | 1,160,464
Restricted Stock Units (RSUs) [Member] |  |
Awards outstanding [Line Items] |  |
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number | 1,799,901 | 1,542,990
Performance Shares [Member] |  |
Awards outstanding [Line Items] |  |
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number | 34,000 | 0
Stock appreciation rights |  |
Awards outstanding [Line Items] |  |
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number | 706,111 | 721,028
Market share units |  |
Awards outstanding [Line Items] |  |
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number | 449,600 | 469,000

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- Definition Number of options outstanding, including both vested and non-vested options. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 Reference 2: 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)-(ii) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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