Stock-Based Compensation Plans (Narrative) (Details) $ in Thousands	9 Months Ended
Sep. 30, 2022 USD ($) shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expensed not yet recognized	$ 18,882
Compensation expensed not yet recognized, period for recognition	2 years 5 months 15 days
ISO and NSO [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Exercise threshold as a percentage of fair value of shares	10.00%
Option term	10 years
Option vesting term	4 years
ISO [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Exercise threshold as a percentage of fair value of shares	100.00%
NSO [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Exercise threshold as a percentage of fair value of shares	85.00%
2019 ESPP
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expensed not yet recognized, period for recognition	1 month 17 days
Common Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Aggregate intrinsic value of options exercised	$ 8,999
Restricted Stock Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Option vesting term	4 years
Compensation expensed not yet recognized, period for recognition	3 years
Unrecognized compensation costs of unvested RSUs	$ 41,198
Maximum [Member] \| ISO and NSO [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Exercise threshold as a percentage of fair value of shares	110.00%
2019 Equity Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares of common stock reserved for issuance (in shares) \| shares	6,417,317
Unrecognized compensation costs related to the ESPP	$ 143
2019 Equity Incentive Plan [Member] \| Common Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Issuance of common stock under employee stock purchase plan (in shares) \| shares	217,502
Shares available for future issuance (in shares) \| shares	1,221,354

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

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