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Stock Compensation Plans (Assumptions Utilized To Estimate The Fair Value For Performance Share Grants) (Details) (USD $)
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3 Months Ended | 12 Months Ended | |
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Jun. 30, 2011
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Mar. 31, 2011
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Dec. 31, 2011
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| Stock Compensation Plans [Abstract] | |||
| Grant Date Market Price | $ 93.85 | $ 96.70 | |
| Average Expected Term (Years) | 2.81 | 2.81 | |
| Expected Volatility | 94.40% | 94.40% | |
| Risk-Free Interest Rate | 1.17% | 1.17% | |
| Dividend Yield | 0.58% | 0.58% | |
| Fair Value | $ 75.64 | $ 77.90 | $ 88.60 |
| Fair Value (Percent of Grant Date Market Price) | 80.60% | 80.60% | |
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- Definition
Share Based Compensation Arrangement by Share Based Payment Award Grant Date Price No definition available.
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- Details
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- Definition
The discount rate from market value on offering date that participants pay for shares. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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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
The period of time an equity-based award is expected to be outstanding. An equity-based award's expected term is generally determined based on, among other factors, the instrument's contractual term and the effects of employees' expected exercise and post-vesting employment termination behavior. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
The estimated measure of the percentage by which a share price is expected to fluctuate during a period. Volatility also may be defined as a probability-weighted measure of the dispersion of returns about the mean. The volatility of a share price is the standard deviation of the continuously compounded rates of return on the share over a specified period. That is the same as the standard deviation of the differences in the natural logarithms of the stock prices plus dividends, if any, over the period. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
The risk-free interest rate assumption that is used in valuing an option on its own shares. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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