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Benefit Plans (Summary Of Non-Qualified Stock Option Activity) (Details) (Non-Qualified Stock Options [Member], USD $)
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9 Months Ended | |
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Sep. 30, 2012
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Sep. 30, 2011
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Non-Qualified Stock Options [Member]
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| Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward] | ||
| Outstanding, January 1, shares (in shares) | 63,889 | 163,680 |
| Outstanding, January 1, weighted average exercise price (in dollars per share) | $ 24.21 | $ 24.51 |
| Exercised, shares (in shares) | (38,711) | (62,481) |
| Exercised, weighted average exercise price (in dollars per share) | $ 24.41 | $ 27.10 |
| Outstanding and exercisable, September 30, shares (in shares) | 25,178 | 101,199 |
| Outstanding and exercisable, September 30, weighted average exercise price (in dollars per share) | $ 23.89 | $ 22.92 |
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- Definition
The weighted average price at which option holders acquired shares when converting their stock options into shares under the plan during the reporting period. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
The number of shares reserved for issuance under stock option agreements awarded under the plan that validly exist and are outstanding as of the balance sheet date, including vested options. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Details
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- Definition
The weighted average price as of the beginning of the year at which grantees can acquire the shares reserved for issuance under the stock option plan. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
Number of share options (or share units) exercised during the current period. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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