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Noncash Share-based Compensation (Details) | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2021 USD ($) $ / shares shares | Sep. 30, 2021 USD ($) $ / shares shares
Noncash Share-based Compensation (Narrative) [Line Items] |  |
Unrecognized compensation cost related to share-based compensation | $ | $ 68,300,000 | $ 68,300,000
Weighted average period to recognize cost, in years |  | 2 years 7 months 6 days
Share-based compensation arrangement by share-based payment, Minimum Employee Subscription rate | 1.00% | 1.00%
Share-based Compensation Arrangement by Share-based Payment Award, Maximum Employee Subscription Rate | 10.00% | 10.00%
Share-based Compensation Arrangement by Share-based Payment Award, Discount from Market Price, Offering Date |  | 15.00%
Maximum Amount Contributable by employees under ESPP- Half yearly | $ |  | $ 5,000
Maximum Amount Contributable By Employees Under ESPP- Annually | $ |  | $ 10,000
Stock Issued During Period, Shares, Employee Stock Purchase Plans | 39,113 | 81,083
ESPP contributions by Employees | $ |  | $ 900,000
RSUs |  |
Noncash Share-based Compensation (Narrative) [Line Items] |  |
Awards, other than options, granted in period | 11,239 | 834,828
Weighted average grant date fair value, per share, of awards granted in period | $ / shares | $ 44.48 | $ 47.54
Employee Stock [Member] |  |
Noncash Share-based Compensation (Narrative) [Line Items] |  |
Shares reserved for issuance under Plan | 1,000,000 | 1,000,000
Shares available for future grants | 493,711 | 493,711
Performance Shares [Member] |  |
Noncash Share-based Compensation (Narrative) [Line Items] |  |
Awards, other than options, granted in period |  | 125,541
Weighted average grant date fair value, per share, of awards granted in period | $ / shares |  | $ 56.05
2017 Equity Incentive Plan [Member] [Member] |  |
Noncash Share-based Compensation (Narrative) [Line Items] |  |
Shares reserved for issuance under Plan | 4,550,000 | 4,550,000
Shares available for future grants | 4,080,355 | 4,080,355
2017 Amended Equity Incentive Plan [Member] |  |
Noncash Share-based Compensation (Narrative) [Line Items] |  |
Shares reserved for issuance under Plan | 7,650,000 | 7,650,000

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- Definition Amount of cost not yet recognized for nonvested 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 (i) -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 + Details
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- Definition Weighted-average period over which cost not yet recognized is expected to be recognized for 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 (i) -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 + Details
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- Definition The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan). + 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 (c)(2)(iii)(1) -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 + Details
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