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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

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- Definition Agreed-upon price for the exchange of the underlying asset relating to the share-based payment award. + References No definition available. + Details
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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 + Details
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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 + Details
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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. + Details
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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 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SAB Topic 14.D.2) -URI http://asc.fasb.org/extlink&oid=115993241&loc=d3e301413-122809 + Details
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- Definition Share-Based Compensation Arrangement By Share-Based Payment Award, Fair Value Assumptions, Weighted Average Fair Value + References No definition available. + Details
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