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Share-Based Compensation (Narrative) (Details) | 6 Months Ended
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Jun. 30, 2012
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |
Performance period of restricted stock units (in years) | 3 years
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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- Definition Performance period of restricted stock and restricted stock units + 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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