Share-Based Compensation - Assumptions For Stock Options (Details) - Stock options	9 Months Ended
Sep. 30, 2021	Sep. 30, 2020
Method and assumptions on valuation of stock options
Expected term of awards (in years)	5 years 8 months 12 days	5 years 7 months 6 days
Expected volatility	32.50%	33.40%
Risk-free interest rate	1.00%	0.50%
Expected dividend yield	0.00%	0.00%

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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- Definition

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

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- Definition

Rate of weighted-average expected volatility for award under share-based payment arrangement.

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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.

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