Cash Equivalents and Marketable Securities - Additional Information (Details) - US Government Agencies Debt Securities $ in Thousands	9 Months Ended		12 Months Ended
	Sep. 30, 2020 USD ($) Security	Sep. 30, 2019 USD ($)	Dec. 31, 2019 USD ($) Security
Cash Equivalents And Marketable Securities [Line Items]
Number of debt securities held | Security	2		13
Allowance for Credit Loss	$ 0		$ 0
Impairment of marketable securities	0		0
Realized gains or losses on marketable securities	0	$ 0
Accrued interest receivable on available-for-sale debt securities	$ 100		$ 300