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Fair Value Measurements and Available for Sale Investments - Schedule of Available for sale Investments by Security Type (Details) $ in Thousands	Sep. 30, 2020 USD ($)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale Investments, Amortized Cost	$ 93,120
Available-for-sale Investments, Gross Unrealized Gains	302
Available-for-sale Investments, Gross Unrealized Losses	0
Available-for-sale Investments, Total Fair Value	93,422
U.S. Treasury and agency securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale Investments, Amortized Cost	35,194
Available-for-sale Investments, Gross Unrealized Gains	0
Available-for-sale Investments, Gross Unrealized Losses	0
Available-for-sale Investments, Total Fair Value	35,194
Commercial paper
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale Investments, Amortized Cost	5,580
Available-for-sale Investments, Gross Unrealized Gains	0
Available-for-sale Investments, Gross Unrealized Losses	0
Available-for-sale Investments, Total Fair Value	5,580
Corporate debt securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale Investments, Amortized Cost	52,346
Available-for-sale Investments, Gross Unrealized Gains	302
Available-for-sale Investments, Gross Unrealized Losses	0
Available-for-sale Investments, Total Fair Value	$ 52,648

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- Definition

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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