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Stock-Based Compensation - Schedule of Grant Date (Details) $ / shares in Units, $ in Millions |  |  |  | 12 Months Ended
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Jun. 24, 2020 USD ($) grantee $ / shares shares | Mar. 16, 2020 USD ($) grantee $ / shares shares | Mar. 20, 2019 USD ($) grantee $ / shares shares | Dec. 31, 2020 $ / shares | Dec. 31, 2019 $ / shares | Dec. 31, 2018 $ / shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Vesting period | 1 year |  |  |  |  |
Stock Option |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Number of grantees affected | grantee |  | 332 | 215 |  |  |
Risk-free rate |  | 0.20% | 0.18% | 0.58% | 2.37% | 2.69%
Stock price (in dollars per share) |  | $ 173.15 | $ 173.15 |  |  |
Volatility |  | 51.32% | 62.29% |  |  |
Shares at target (in shares) | shares |  | 199,870 | 86,845 |  |  |
Fair value per share (in dollars per share) |  | $ 280.93 | $ 188.21 | $ 35.13 | $ 58.28 | $ 51.27
Total incremental compensation cost | $ |  | $ 21.8 | $ 1.3 |  |  |
Vesting period |  |  |  | 3 years |  |
Stock Options, Non-CEO |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Number of grantees affected | grantee | 134 |  |  |  |  |
Risk-free rate | 0.21% |  |  |  |  |
Stock price (in dollars per share) | $ 160.14 |  |  |  |  |
Volatility | 47.72% |  |  |  |  |
Shares at target (in shares) | shares | 110,467 |  |  |  |  |
Fair value per share (in dollars per share) | $ 264.17 |  |  |  |  |
Total incremental compensation cost | $ | $ 11.5 |  |  |  |  |
Stock Options, CEO |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Number of grantees affected | grantee | 1 |  |  |  |  |
Risk-free rate | 0.21% |  |  |  |  |
Stock price (in dollars per share) | $ 160.14 |  |  |  |  |
Volatility | 47.72% |  |  |  |  |
Shares at target (in shares) | shares | 28,101 |  |  |  |  |
Fair value per share (in dollars per share) | $ 240.55 |  |  |  |  |
Total incremental compensation cost | $ | $ 2.3 |  |  |  |  |

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- Definition Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition. + 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 (a)(1) -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 Rate of weighted-average expected volatility for award under share-based payment arrangement. + 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 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 An excess of the fair value of the modified award over the fair value of the award immediately before the modification. + 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 (h)(2)(iii) -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 + Details
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