Fair Value Measurements and Available for Sale Investments (Tables)

9 Months Ended

Sep. 30, 2020

Fair Value Measurements And Available For Sale Investments [Abstract]

Assets Measured at Fair Value on Recurring Basis

The following table presents the hierarchy for assets measured at fair value on a recurring basis as of September 30, 2020 and December 31, 2019 (in thousands):


	Fair Value Measurements at End of Period Using:
	Total Fair Value		Quoted Market Prices for Identical Assets (Level 1)		Significant Other Observable Inputs (Level 2)		Significant Unobservable Inputs (Level 3)
As of September 30, 2020
Money market funds	$	367,344	$	367,344	$	—	$	—
U.S. Treasury and agency securities	53,772		53,772		—		—
Commercial paper	5,580		—		5,580		—
Corporate debt securities	53,897		—		53,897		—
As of December 31, 2019
Money market funds	$	82,125	$	82,125	$	—	$	—
U.S. Treasury and agency securities	91,717		91,717		—		—
Commercial paper	37,411		—		37,411		—
Corporate debt securities	156,277		—		156,277		—

Schedule of Available for Sale Investments by Security Type

The aggregate market value, cost basis, and gross unrealized gains and losses of available-for-sale investments by security type, classified in marketable securities and long-term investments as of September 30, 2020 are as follows (in thousands):


	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses		Total Fair Value
Marketable securities
U.S. Treasury and agency securities	$	35,194	$	—	$	—	$	35,194
Commercial paper	5,580		—		—		5,580
Corporate debt securities	52,346		302		—		52,648
Total marketable securities	$	93,120	$	302	$	—	$	93,422

Schedule of Contractual Maturities of Available-for-sale Debt Securities

Contractual maturities of available-for-sale debt securities, as of September 30, 2020, were as follows (in thousands):


	Estimated Fair Value
Due within one year	$	79,582
One to two years	13,840
Total	$	93,422