Long-term Equity-based Compensation - Black-Scholes Pricing Model For Options (Details) - Stock Options	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected volatility rate, minimum	29.22%	28.97%	27.31%
Expected volatility rate, maximum	37.27%	33.78%	32.15%
Risk-free interest rate, minimum	0.17%	1.35%	2.44%
Risk-free interest rate, maximum	1.46%	2.60%	3.00%
Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected dividend yield rate	1.19%	1.05%	1.16%
Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected dividend yield rate	1.48%	1.38%	1.72%
Employee \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted-average expected life (in years)	4 years	4 years	4 years
Employee \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted-average expected life (in years)	6 years	6 years	6 years

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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- Definition

The estimated measure of the maximum 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.

+ References

No definition available.

+ Details

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The estimated measure of the minimum 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.

+ References

No definition available.

+ Details

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- Definition

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

+ References

No definition available.

+ Details

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- Definition

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

+ References

No definition available.

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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.

+ References

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

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