Noncash Share-based Compensation (Details)	3 Months Ended	6 Months Ended
Jun. 30, 2020 USD ($) $ / shares shares	Jun. 30, 2020 USD ($) $ / shares shares
Noncash Share-based Compensation (Narrative) [Line Items]
Unrecognized compensation cost related to share-based compensation \| $	$ 59,600,000	$ 59,600,000
Weighted average period to recognize cost, in years		2 years 10 months 24 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	0	26,774
ESPP contributions by Employees \| $		$ 1,500,000
RSUs
Noncash Share-based Compensation (Narrative) [Line Items]
Awards, other than options, granted in period	173,060	632,559
Weighted average grant date fair value, per share, of awards granted in period \| $ / shares	$ 31.29	$ 56.67
Employee Stock [Member]
Noncash Share-based Compensation (Narrative) [Line Items]
Shares available for future grants	113,477	113,477
Performance Shares [Member]
Noncash Share-based Compensation (Narrative) [Line Items]
Awards, other than options, granted in period		76,200
Weighted average grant date fair value, per share, of awards granted in period \| $ / shares		$ 54.23
2017 Equity Incentive Plan [Member] [Member]
Noncash Share-based Compensation (Narrative) [Line Items]
Shares reserved for issuance under Plan	2,500,000	2,500,000
Shares available for future grants	1,857,201	1,857,201
2017 Amended Equity Incentive Plan [Member]
Noncash Share-based Compensation (Narrative) [Line Items]
Shares reserved for issuance under Plan	4,550,000	4,550,000

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Share-based compensation arrangement by share-based payment, Minimum Employee Subscription rate

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Amount of cost not yet recognized for nonvested award under share-based payment arrangement.

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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.

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Discount rate from fair value on offering date that participants pay for shares.

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The number of grants made 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).

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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).

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The highest percentage of annual salary that an employee is permitted to utilize with respect to the plan.

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The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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Number of shares issued during the period as a result of an employee stock purchase plan.

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