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Share-Based Compensation (Schedule Of Performance Vesting Restricted Stock Units Granted) (Details) | 6 Months Ended | 12 Months Ended
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Jun. 30, 2013 | Dec. 31, 2012 | Dec. 31, 2011
Share-based Compensation, Allocation and Classification in Financial Statements [Abstract] |  |  |  |  |  |
Three-year performance period ending December 31, | 2015 |  | 2014 |  | 2013 |
Vesting shares, target | 84,500 | [1] | 89,000 | [1] | 80,000 | [1]
Vesting shares, maximum | 190,125 | [1] | 200,250 | [1] | 120,000 | [1]
[1] |

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- Definition Performance vesting restricted stock units, three-year performance period ending, years. + References No definition available. + Details
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- Definition Performance vesting restricted stock units, vesting shares, maximum. + References No definition available. + Details
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- Details
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- Definition The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan). + 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)(2)(iii)(1) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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