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Stock-Based Compensation - Schedule of Assumptions Used (Details) - $ / shares			12 Months Ended
	Mar. 16, 2020	Mar. 20, 2019	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Performance Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Exercise price (in dollars per share)			$ 99.69
Expected stock price volatility			31.14%
Risk-free interest rate			2.18%
Weighted average fair value (in dollars per share)			$ 28.69
Stock Option
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Exercise price (in dollars per share)			$ 109.66	$ 184.81	$ 158.23
Expected stock price volatility			32.37%	27.21%	27.35%
Risk-free interest rate	0.20%	0.18%	0.58%	2.37%	2.69%
Weighted average fair value (in dollars per share)	$ 280.93	$ 188.21	$ 35.13	$ 58.28	$ 51.27
Weighted average expected term (in years)			6 years	6 years	6 years

X

- Definition

Agreed-upon price for the exchange of the underlying asset relating to the share-based payment award.

+ References

No definition available.

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- Definition

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.

+ References

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)(ii)
-URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901

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- Definition

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

+ References

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)(iv)
-URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901

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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
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (f)(2)(i)
-URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901

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-Name Accounting Standards Codification
-Topic 718
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- Definition

Share-Based Compensation Arrangement By Share-Based Payment Award, Fair Value Assumptions, Weighted Average Fair Value

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