Cash, Cash Equivalents and Marketable Securities

12 Months Ended

Dec. 31, 2020

Cash and Cash Equivalents [Abstract]

Cash, Cash Equivalents and Marketable Securities

The following table summarizes the amortized cost and fair value of our cash, cash equivalents and marketable securities by major investment category as of December 31, 2020 and 2019:


	December 31, 2020
(In thousands)	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses		Estimated Fair Value
Current assets:
Cash	$	23,887	$	—	$	—	$	23,887
Cash equivalents:
Money market funds	80,986		—		—		80,986
Commercial paper	61,043		—		—		61,043
Certificate of deposits	1,000		—		—		1,000
Total cash equivalents	143,029		—		—		143,029
Total cash and cash equivalents	166,916		—		—		166,916
Marketable securities:
U.S. Treasuries	43,050		1		(1)		43,050
Commercial paper	210,986		—		—		210,986
Certificate of deposits	44,480		—		—		44,480
U.S. Government-sponsored enterprises debt securities	6,200		17		—		6,217
Corporate debt securities	33,288		172		—		33,460
Total marketable securities	338,004		190		(1)		338,193
Total cash, cash equivalents and marketable securities	$	504,920	$	190	$	(1)	$	505,109


	December 31, 2019
(In thousands)	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses		Estimated Fair Value
Current assets:
Cash	$	43,058	$	—	$	—	$	43,058
Cash equivalents:
Money market funds	11,527		—		—		11,527
Commercial paper	7,485		—		—		7,485
Total cash and cash equivalents	62,070		—		—		62,070
Marketable securities:
Commercial paper	73,366		—		—		73,366
Corporate debt securities	74,038		381		(2)		74,417
Certificates of deposit	41,302		—		—		41,302
Total marketable securities	188,706		381		(2)		189,085
Total cash, cash equivalents and marketable securities	$	250,776	$	381	$	(2)	$	251,155

The following table summarizes the amortized cost and fair value of marketable securities based on stated effective maturities as of December 31, 2020:


(In thousands)	Amortized Cost		Estimated Fair Value
Due within one year	$	331,804	$	331,976
Due between one and two years	6,200		6,217
Total	$	338,004	$	338,193

We regularly review our available-for-sale marketable securities in an unrealized loss position and evaluate the current expected credit loss by considering factors such as historical experience, market data, issuer-specific factors, and current economic conditions. As of December 31, 2020, no provision for current expected credit losses was required as the fair value of each individual security in an unrealized loss position exceeded its amortized cost by a de minimis amount.

Accrued interest receivable on available-for-sale marketable securities are recorded within prepaid expenses and other current assets on our consolidated balance sheets and was $0.3 million and $0.6 million at December 31, 2020 and 2019, respectively.

See Note 7 for further information regarding the fair value of our financial instruments.