Fair Value Measurements and Available for Sale Investments (Tables)

9 Months Ended

Sep. 30, 2020

Schedule of Assets and Liabilities that Require Fair Value Measurements on a Recurring Basis

The following table summarizes our assets and liabilities that require fair value measurements on a recurring basis and their respective input levels based on the fair value hierarchy:


	Fair Value Measurements at End of Period Using:
(in thousands)	Fair Value		Quoted Market Prices for Identical Assets (Level 1)		Significant Other Observable Inputs (Level 2)		Significant Unobservable Inputs (Level 3)
At September 30, 2020
Money market funds(1)	$	204,678	$	204,678	$	—	$	—
Mutual funds(1)	4,833		4,833		—		—
U.S. Treasury securities(2)	107,159		107,159		—		—
Certificates of deposit(2)	3,713		—		3,713		—
Agency securities(2)	15,805		—		15,805		—
Commercial and corporate obligations(2)	38,692		—		38,692		—

At December 31, 2019
Money market funds(1)	$	162,928	$	162,928	$	—	$	—
Mutual funds(1)	7,619		7,619		—		—
U.S. Treasury securities(2)	96,434		96,434		—		—
Certificates of deposit(2)	5,428		—		5,428		—
Agency securities(2)	33,623		—		33,623		—
Commercial and corporate obligations(2)	122,030		—		122,030		—

(1) Included in cash and cash equivalents or restricted cash in the accompanying consolidated balance sheets.

(2) Included in short-term or long-term investments in the accompanying consolidated balance sheets depending on the respective maturity date.

Fair Value of Other Financial Instruments

The fair value of our other financial instruments estimated as of September 30, 2020 and December 31, 2019 are presented below:


	September 30, 2020				December 31, 2019
(in thousands)	Carrying Amount		Fair Value		Carrying Amount		Fair Value
Notes payable	$	—	$	—	$	1,375	$	1,365

Available-for-sale Investments

The aggregate market value, cost basis, and gross unrealized gains and losses of available-for-sale investments by security type, classified in cash equivalents, short-term 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
Agency securities(1)	$	15,790	$	16	$	(1)	$	15,805

Certificates of deposit(2)	3,696		17		—		3,713
Commercial and corporate obligations(3)	38,590		105		(3)		38,692
U.S. Treasury securities(4)	106,826		343		(10)		107,159
Total available-for-sale investments	$	164,902	$	481	$	(14)	$	165,369

(1) Of our outstanding agency securities, $0.8 million have maturity dates of less than one year and $15.0 million have a maturity date of between one to two years as of September 30, 2020.

(2) Of our outstanding certificates of deposit, $3.0 million have maturity dates of less than one year and $0.7 million have a maturity date of between one to two years as of September 30, 2020.

(3) All of our outstanding commercial and corporate obligations have maturity dates of less than one year as of September 30, 2020.

(4) Of our outstanding U.S. Treasury securities, $86.7 million have maturity dates of less than one year and $20.4 million have a maturity date of between one to two years as of September 30, 2020.

Schedule of Unrealized Loss and Fair Values in a Loss Position

The following tables present gross unrealized losses and fair values for those investments that were in an unrealized loss position as of September 30, 2020 and December 31, 2019, aggregated by investment category and the length of time that individual securities have been in a continuous loss position:


	September 30, 2020
	Less than 12 Months				12 Months or Greater				Total
(in thousands)	Fair Value		Gross Unrealized Losses		Fair Value		Gross Unrealized Losses		Fair Value		Gross Unrealized Losses
Agency securities	$	9,998	$	(1)	$	—	$	—	$	9,998	$	(1)
Commercial and corporate obligations	4,096		(3)		—		—		4,096		(3)
US Treasury Securities	25,223		(10)		—		—		25,223		(10)
Total	$	39,317	$	(14)	$	—	$	—	$	39,317	$	(14)


	December 31, 2019
	Less than 12 Months				12 Months or Greater				Total
(in thousands)	Fair Value		Gross Unrealized Losses		Fair Value		Gross Unrealized Losses		Fair Value		Gross Unrealized Losses
Commercial and corporate obligations	$	5,986	$	(4)	$	—	$	—	$	5,986	$	(4)
US Treasury Securities	17,608		(2)		—		—		17,608		(2)
Total	$	23,594	$	(6)	$	—	$	—	$	23,594	$	(6)