Share-Based Compensation - Summary of Assumptions (Details) - USD ($)	6 Months Ended
Jun. 30, 2021	Jun. 30, 2020
Performance Award
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected dividend rate	$ 0.38
Expected volatility	39.10%
Risk-free interest rate	0.28%
Expected life	2 years 9 months 18 days
Directors and Senior Leadership Team
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected dividend rate	$ 0.38	$ 0.33
Expected volatility	35.78%	31.63%
Risk-free interest rate	0.51%	0.64%
Expected life	4 years	5 years
Employees
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected dividend rate	$ 0.38	$ 0.32
Expected volatility	38.70%	31.23%
Risk-free interest rate	0.30%	0.69%
Expected life	3 years	5 years

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

Disclosure of the weighted average expected dividend for an entity using a valuation technique with different dividend rates during the contractual term.

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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.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (f)(2)(i)
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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section S99
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-Subparagraph (SAB Topic 14.D.2)
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