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Summary Of Significant Accounting Policies - Accounting for Stock-Based Compensation (Details) | 12 Months Ended
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Dec. 31, 2012
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |
Expiration period | 10 years
Maximum [Member] |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |
Vesting period | 5 years
Stock Options [Member] | Minimum [Member] |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |
Vesting period | 3 years
Restricted Stock [Member] | Minimum [Member] |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |
Vesting period | 3 years
Restricted Stock [Member] | Maximum [Member] |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |
Vesting period | 5 years

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- Definition Share-based Compensation Arrangement by Share-based Payment Award, Expiration Period + References No definition available. + Details
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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 + Details
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- Details
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