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Stock-Based Compensation (Schedule of Weighted Average Assumptions for Restricted Stock Units) (Details) (Restricted Stock Units (RSUs) [Member], USD $)
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12 Months Ended | ||
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Dec. 31, 2012
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Dec. 31, 2011
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Dec. 31, 2010
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Restricted Stock Units (RSUs) [Member]
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| Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | |||
| Vesting period | 3 years 10 months 10 days | 3 years 11 months 16 days | 3 years 9 months |
| Expected dividend yield | 1.77% | 1.33% | 1.56% |
| Estimated average fair value per restricted stock unit granted | $ 46.57 | $ 58.37 | $ 43.95 |
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- Definition
The weighted average fair value at grant date for nonvested equity-based awards issued 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). Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
The estimated dividend rate (a percentage of the share price) to be paid (expected dividends) to holders of the underlying shares over the option's term. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
Expected term of share-based compensation awards, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Details
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