Stock Incentive Plans - PBUs, Valuation Assumptions (Details) - Performance Based Units	9 Months Ended
Sep. 30, 2019	Sep. 30, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected Term (Remaining Performance Period)	2 years 10 months 9 days	2 years 10 months 9 days
Expected volatility	28.46%	28.56%
Risk-free interest rate	2.48%	2.38%
Expected dividends	0.00%	0.00%
Correlation coefficient	54.81%	38.98%
Average correlation coefficient of constituents	57.09%	39.96%

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 share-based compensation awards, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
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