Stock-Based Compensation - Total Unrecognized Stock-Based Compensation Expense and Expected Period Over Which Such Expense Will Be Recognized (Details) $ in Millions	3 Months Ended
Mar. 31, 2022 USD ($)
Stock Options
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Unrecognized stock compensation expense	$ 34.5
Weighted-average remaining vesting period (years)	2 years 10 months 24 days
Restricted Stock Units ("RSU")
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Weighted-average remaining vesting period (years)	2 years 3 months 18 days
Unrecognized stock compensation expense	$ 14.8
2015 ESPP
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Weighted-average remaining vesting period (years)	1 month 6 days
Unrecognized stock compensation expense	$ 0.1

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.

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

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