Stock Option Plans (Narrative) (Details) - USD ($) $ in Thousands	1 Months Ended	9 Months Ended
Mar. 31, 2019	Sep. 30, 2021
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expensed not yet recognized		$ 19,994
Compensation expensed not yet recognized, period for recognition		2 years 7 months 6 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%
Common Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Aggregate intrinsic value of options exercised		$ 25,146
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 2 months 4 days
Unrecognized compensation costs of unvested RSUs		$ 15,830
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)	2,317,000	5,015,486
Common stock reserved for future issuance (in shares)	434,000
Percent of purchase of price of common stock	1.00%
Compensation expensed not yet recognized, period for recognition		1 month 17 days
Unrecognized compensation costs related to the ESPP		$ 105
2019 Equity Incentive Plan [Member] \| Scenario, Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of additional shares allowable under the plan (in shares)		3,000,000
Percent of outstanding shares of common stock		4.00%
2019 Equity Incentive Plan [Member] \| Common Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock reserved for future issuance (in shares)		1,089,048
Percent of purchase of price of common stock		85.00%
Issuance of common stock under employee stock purchase plan (in shares)		141,059
Shares available for future issuance (in shares)		947,989
2019 Equity Incentive Plan [Member] \| Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock reserved for future issuance (in shares)	1,200,000

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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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Maximum number of shares that may be issued in accordance with the plan as a proportion of outstanding capital stock.

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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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