Marketable Securities

12 Months Ended

Dec. 31, 2019

Marketable Securities

Marketable Securities

4. Marketable Securities

The following table summarizes the Company’s investments as of December 31, 2019 (in thousands):

			Gross
	Amortized		Unrealized				Estimated
	Cost		Gains		Losses		Fair Value
Marketable securities available-for-sale:
U.S. Treasury obligations	$	121,103	$	39	$	(2)	$	121,140
Total available-for-sale securities	$	121,103	$	39	$	(2)	$	121,140

The following table summarizes the Company’s investments as of December 31, 2018 (in thousands):

			Gross
	Amortized		Unrealized				Estimated
	Cost		Gains		Losses		Fair Value
Marketable securities available-for-sale:
U.S. Treasury obligations	$	60,584	$	—	$	(8)	$	60,576
Total available-for-sale securities	$	60,584	$	—	$	(8)	$	60,576

The aggregate fair value of marketable securities with unrealized losses was $19.6 million and $60.6 million at December 31, 2019 and 2018, respectively. At December 31, 2019 and 2018, 3 investments and 16 investments, respectively, were in an unrealized loss position. All such investments have been in an unrealized loss position for less than a year and these losses are considered temporary. The Company has the ability and intent to hold these investments until a recovery of their amortized cost, which may be until maturity.