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Stock Option and Purchase Plans (Details) (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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| Summary of weighted average fair value of the options granted | |||
| Weighted Average Fair Value of the Options Granted | $ 11.91 | $ 15.18 | $ 8.12 |
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- Details
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- Definition
The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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