Share-Based Compensation - Narrative (Details) $ in Millions	3 Months Ended
Mar. 31, 2021 USD ($) shares
Share-Based Compensation [Line Items]
Unrecognized share-based compensation expense related to stock options \| $	$ 4.0
Options and RSUs \| Non-employee director
Share-Based Compensation [Line Items]
Service period for award vesting (in years)	1 year
Stock options
Share-Based Compensation [Line Items]
Service period for award vesting (in years)	4 years
Weighted-average period for recognition of share-based compensation expense (in years)	2 years 3 months 18 days
Stock options \| Awards granted after December 5, 2012
Share-Based Compensation [Line Items]
Award expiration period (in years)	8 years
Stock options \| Awards granted prior to December 5, 2012
Share-Based Compensation [Line Items]
Award expiration period (in years)	10 years
RSUs
Share-Based Compensation [Line Items]
Service period for award vesting (in years)	4 years
Unrecognized share-based compensation expense related to RSUs \| $	$ 89.5
Weighted-average period for recognition of share-based compensation expense (in years)	2 years 9 months 18 days
2017 Plan
Share-Based Compensation [Line Items]
Shares available for grant	3,300,000
2012 Purchase Plan
Share-Based Compensation [Line Items]
Number of shares authorized	2,000,000.0
Shares available for issuance under the Plan	200,000

Aggregate number of common shares reserved for future issuance.

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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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Amount of cost to be recognized for nonvested award under share-based payment arrangement. Excludes share and unit options.

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Amount of cost to be recognized for option under share-based payment arrangement.

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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.

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Number of shares authorized for issuance under share-based payment arrangement.

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Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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