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Stock Based Compensation (Details)		3 Months Ended		88 Months Ended
	Dec. 02, 2013 shares	Mar. 31, 2021 item shares	Mar. 31, 2020 shares	Mar. 31, 2021 shares	Jan. 01, 2021 shares
Employee stock options
Stock-based compensation
Options granted (in shares)		1,321,917	1,137,420
ESPP
Stock-based compensation
Total number of shares of common stock available for issuance		581,286		581,286
Awards issued under the plan (in shares)				467,595
Increase in shares of common stock available for issuance (in shares)		0
ESPP | Maximum
Stock-based compensation
Annual percentage increase in shares of common stock available for issuance		1.00%
Annual increase in shares of common stock available for issuance (in shares)		621,814
Restricted stock units
Stock-based compensation
Awards issued under the plan (in shares)				700,837
Granted		247,050
Annual installment vesting periods | item		3
The 2013 Plan
Stock-based compensation
Total number of shares of common stock available for issuance		13,445,524		13,445,524	2,314,937
Annual percentage increase in shares of common stock available for issuance		4.00%
Awards issued under the plan (in shares)				11,894,756
Increase in shares of common stock available for issuance (in shares)		2,314,937
The 2010 Plan
Stock-based compensation
Total number of shares of common stock available for issuance		2,684,456		2,684,456
Options granted (in shares)	0

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