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Share-Based Compensation - Additional Information (Details) - USD ($) $ / shares in Units, $ in Thousands	1 Months Ended	9 Months Ended
	Oct. 31, 2020	Sep. 30, 2020	Dec. 31, 2019
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of common stock available for issuance		5,355,893
Other long-term liabilities		$ 96	$ 134
Unrecognized compensation cost		$ 18,300
Unrecognized compensation cost, expected to be recognized over weighted average remaining service period		3 years 4 months 24 days
Subsequent Event \| Separation and Release Agreement \| Matthew Plunkett
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Estimated share-based compensation expense	$ 2,200
Severance benefits expense	$ 300
Agreement execution date	Oct. 02, 2020
Period in which severance benefits payable after termination date	6 months
Restricted Stock Options
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares subject to repurchase		107,847	132,249
Other long-term liabilities		$ 100	$ 100
2020 Employee Stock Purchase Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares issued		0
Number of common stock available for issuance		295,599
Maximum percentage of employee compensation eligible for plan		15.00%
Offering period		6 months
Commons stock purchase price as percentage of fair value		85.00%
2015 Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares issued		2,364,268
2020 Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of common stock authorized for issuance		2,660,371
Increase in share limit as percentage of outstanding shares of common stock on last trading day in prior year		5.00%
Number of awards granted		1,239,532
Number of common stock available for issuance		1,495,314
2020 Plan and 2015 Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Weighted-average grant date fair value		$ 10.34