Stock Incentive Plans - PBUs, Valuation Assumptions (Details) - Performance Based Units	6 Months Ended
Jun. 30, 2020	Jun. 30, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected Term (Remaining Performance Period)	2 years 10 months 6 days	2 years 10 months 9 days
Expected volatility	29.85%	28.46%
Risk-free interest rate	1.21%	2.48%
Expected dividends	0.00%	0.00%
Correlation coefficient	53.43%	54.81%
Median correlation coefficient of constituents	54.01%	57.09%

Share-based Compensation Arrangement By Share-Based Payment Award, Fair Value Assumptions, Correlation Coefficient

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- Definition

Share-based Compensation Arrangement By Share-based Payment Award, Fair Value Assumptions, Average Correlation Coefficient Of Constituents

+ References

No definition available.

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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.

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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.

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- Definition

The risk-free interest rate assumption that is used in valuing an option on its own shares.

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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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No definition available.

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- Definition

Expected term of award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
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