Earnings Per Share and Capital Structure Convertible Notes (Details) (USD $) In Thousands, except Per Share data | 3 Months Ended | 9 Months Ended | ||
|---|---|---|---|---|
Sep. 30, 2011 | Sep. 30, 2010 | Sep. 30, 2011 | Sep. 30, 2010 | |
| Earnings Per Share, Diluted, by Common Class, Including Two Class Method [Line Items] | ||||
| Incremental Common Shares Attributable to Conversion of Debt Securities | 0 | 0 | 0 | 138 |
| Debt instrument, convertible, conversion price | $ 65.16 | $ 65.16 | ||
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- Definition The price per share of the conversion feature embedded in the debt instrument. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.
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- Definition Additional shares included in the calculation of diluted EPS as a result of the potentially dilutive effect of convertible debt securities using the if-converted method. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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