Share-Based Compensation and Other Compensation Matters (Details 3) - Performance share units [Member] - $ / shares |
12 Months Ended | ||
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Dec. 31, 2015 |
Dec. 31, 2014 |
Dec. 31, 2013 |
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| Potential earned PSUs payout for defined levels of performance under awards | |||
| Earned PSUs payout (as a percent of PSUs granted) on 75th or greater percentile rank | 200.00% | ||
| Earned PSUs payout (as a percent of PSUs granted) on 50th percentile rank | 100.00% | ||
| Earned PSUs payout (as a percent of PSUs granted) on 25th percentile rank | 50.00% | ||
| Performance share units granted on percentile rank below 25th (as a percent) | 0.00% | ||
| Assumptions used to value stock awards | |||
| Grant date fair value (in dollars per share) | $ 36.76 | $ 35.09 | $ 26.84 |
| Baseline value per common share (in dollars per share) | $ 29.28 | $ 26.52 | $ 25.85 |
| Expected volatility of common shares (as a percent) | 19.90% | 28.60% | 29.50% |
| Risk-free interest rate (as a percent) | 0.99% | 0.66% | 0.33% |
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- References No definition available.
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- Definition Represents the baseline common share value that is used in valuing the grant date fair value of awards. No definition available.
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- Definition Represents the earned performance share units payout, as a percentage of performance share units granted, if the entity's total shareholder return relative to a peer group of companies ranks at the 25th percentile. No definition available.
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- Definition Represents the earned performance share units payout, as a percentage of performance share units granted, if the entity's total shareholder return relative to a peer group of companies ranks at the 50th percentile. No definition available.
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- Definition Represents the earned performance share units payout, as a percentage of performance share units granted, if the entity's total shareholder return relative to a peer group of companies ranks at the 75th percentile or greater. No definition available.
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- Definition Represents the earned performance share units payout percentage based on percentile rank below 25. No definition available.
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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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- References No definition available.
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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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- Details
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