Fair Value Measurements and Available for Sale Investments (Tables)

6 Months Ended

Jun. 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 June 30, 2020 and December 31, 2019 (in thousands):

	Fair Value Measurements at End of Period Using:
				Quoted Market		Significant		Significant
				Prices for		Other Observable		Unobservable
		Total		Identical Assets		Inputs		Inputs
		Fair Value		(Level 1)		(Level 2)		(Level 3)
As of June 30, 2020
Money market funds		$	365,982	$	365,982	$	—	$	—
U.S. Treasury and agency securities			6,175		6,175		—		—
Commercial paper			25,213		—		25,213		—
Corporate debt securities			82,914		—		82,914		—
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 June 30, 2020 are as follows (in thousands):

			Gross		Gross
	Amortized		Unrealized		Unrealized		Total
	Cost		Gains		Losses		Fair Value
Marketable securities
U.S. Treasury and agency securities	$	6,160	$	15	$	—	$	6,175
Commercial paper		25,213		—		—		25,213
Corporate debt securities		82,335		579		—		82,914
Total marketable securities	$	113,708	$	594	$	—	$	114,302

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

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

	Estimated
	Fair Value
Due within one year	$	100,376
One to two years		13,926
Total	$	114,302