Cash Equivalents and Marketable Securities

12 Months Ended

Dec. 31, 2021

Investments, Debt and Equity Securities [Abstract]

Cash Equivalents and Marketable Securities

Cash Equivalents and Marketable Securities

Cash equivalents and available-for-sale debt securities consisted of the following as of December 31, 2021 and 2020 (in thousands):

	December 31, 2021
	Amortized Cost		Unrealized Gains		Unrealized Losses		Fair Value
Cash equivalents:
Money market funds	$	684,485	$	—	$	—	$	684,485
U.S. treasury securities	22,000		—		—		22,000
U.S. government agency securities	4,286		—		(1)		4,285
Corporate debt securities	15,998		—		—		15,998
Total cash equivalents	726,769		—		(1)		726,768
Debt securities:
U.S. treasury securities	442,715		2		(432)		442,285
U.S. government agency securities	75,725		—		(159)		75,566
Corporate debt securities	54,335		17		(175)		54,177
Total debt securities	572,775		19		(766)		572,028
Total cash equivalents and debt securities	$	1,299,544	$	19	$	(767)	$	1,298,796

	December 31, 2020
	Amortized Cost		Unrealized Gains		Unrealized Losses		Fair Value
Cash equivalents:
Money market funds	$	56,474	$	—	$	—	$	56,474
Debt Securities:
U.S. treasury securities	50,087		136		—		50,223
Corporate debt securities	85,413		265		(5)		85,673
Asset-backed securities	3,247		15		—		3,262
Total debt securities	138,747		416		(5)		139,158
Total cash equivalents and debt securities	$	195,221	$	416	$	(5)	$	195,632

As of December 31, 2021 and 2020, there were no securities that have been in a continuous unrealized loss position for 12 months or longer.

The amortized cost and fair value of the available-for-sale debt securities based on contractual maturities are as follows (in thousands):

	December 31, 2021
	Amortized Cost		Fair Value
Due within one year	$	392,629	$	392,412
Due after one year but within five years	180,146		179,616
Total	$	572,775	$	572,028

In addition to available-for-sale debt securities, marketable securities also include term bond mutual funds, which are measured at fair value. As of December 31, 2021 and 2020, the fair value of the term bond mutual funds was $3.7 million and $3.6 million, respectively.

The change in fair value of the term bond mutual funds is recorded in interest and other income, net in the consolidated statements of operations. The following table summarizes the realized and unrealized gains recognized in the consolidated

statements of operations for the term bond mutual funds during the years ended December 31, 2021, 2020, and 2019 (in thousands):

	Year Ended December 31,
	2021		2020		2019
Net gains recognized on marketable equity investments	$	132	$	107	$	582
Less: Net gains recognized on sale of marketable equity investments	—		—		(316)
Unrealized gains at the end of the period	$	132	$	107	$	266

Non-Marketable Equity Securities

Non-marketable equity securities represent the Company’s interest in privately held entities which have no readily determinable fair values. The Company carries these investments at cost, less impairment, and reports them under other assets in the consolidated balance sheets. As of December 31, 2021 and 2020, the Company had non-marketable equity securities of $0.4 million and $0.5 million, respectively.

In September 2021, the Company sold its interest in a privately held entity for proceeds totaling $24.0 million, resulting in a gain of $23.8 million, which was recorded in interest and other income, net, in the consolidated statements of operations.