Cash Equivalents and Short-Term Investments - Summary of Amortized Cost and Fair Value (Details) - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	$ 29,051	$ 36,876
Gross unrealized gains	0	16
Gross unrealized losses	0	0
Fair market value	29,051	36,892
Money market funds
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	27,053	9,995
Gross unrealized gains	0	0
Gross unrealized losses	0	0
Fair market value	27,053	9,995
U.S. treasury bills
Debt Securities, Available-for-sale [Line Items]
Amortized Cost		5,019
Gross unrealized gains		2
Gross unrealized losses		0
Fair market value		5,021
Corporate debt securities and commercial paper
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	1,998	21,862
Gross unrealized gains	0	14
Gross unrealized losses	0	0
Fair market value	$ 1,998	$ 21,876

Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amount, before tax, of unrealized loss in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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