Investments

12 Months Ended

Dec. 31, 2023

Investments, Debt and Equity Securities [Abstract]

The following table summarizes our cash equivalents and available-for-sale debt investments:


	December 31, 2023
									Fair Value Level
	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses (1)		Total Fair Value		Level 1		Level 2
	(In thousands)
Cash equivalents
Asset-backed securities	$	138	$	—	$	—	$	138	$	—	$	138

Commercial paper	48,063		—		—		48,063		—		48,063

Money market funds	60,719		—		—		60,719		60,719		—

U.S. government bonds	2,996		—		—		2,996		2,996		—

Total cash equivalents (2)	111,916		—		—		111,916		63,715		48,201

Short-term investments
Asset-backed securities	65,340		170		(22)		65,488		—		65,488
Certificate of deposits	17,086		—		—		17,086		17,086		—
Commercial paper	56,273		—		—		56,273		—		56,273
Corporate bonds	251,671		432		(299)		251,804		—		251,804



U.S. government agency bonds	13,200		—		(9)		13,191		—		13,191
U.S. government bonds	65,881		13		(79)		65,815		65,815		—


Total short-term investments	469,451		615		(409)		469,657		82,901		386,756
Total	$	581,367	$	615	$	(409)	$	581,573	$	146,616	$	434,957


	December 31, 2022
									Fair Value Level
	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses (1)		Total Fair Value		Level 1		Level 2
	(In thousands)
Cash equivalents
Asset-backed securities	$	25	$	—	$	—	$	25	$	—	$	25
Commercial paper	69,101		—		—		69,101		—		69,101

Money market funds	97,650		—		—		97,650		97,650		—
Municipal bonds	1,001		—		—		1,001		—		1,001
US government bonds	10,767		1		—		10,768		10,768		—
US government agency bonds	16,982		3		—		16,985		—		16,985
Total cash equivalents (2)	195,526		4		—		195,530		108,418		87,112
Short-term investments
Asset-backed securities	25,677		7		(134)		25,550		—		25,550
Certificate of deposits	17,362		—		—		17,362		17,362		—
Commercial paper	27,866		—		—		27,866		—		27,866
Corporate bonds	198,868		7		(1,529)		197,346		—		197,346
Foreign government bonds	996		—		(4)		992		—		992
Mortgage-backed securities	696		—		(2)		694		—		694
Municipal bonds	364		—		(2)		362		—		362
U.S. government agency bonds	735		—		(1)		734		—		734
U.S. government bonds	6,704		1		(20)		6,685		6,685		—

Total short-term investments	279,268		15		(1,692)		277,591		24,047		253,544
Total	$	474,794	$	19	$	(1,692)	$	473,121	$	132,465	$	340,656

(1)All unrealized losses have been in a continuous loss position for less than 12 months. We do not intend to sell the investments in an unrealized loss position, and we do not believe it is more likely than not that we will be required to sell these investments before recovery of their amortized cost bases.

(2)During the years ended December 31, 2023, 2022, and 2021 we sold cash equivalent investments for proceeds of $47.0 million, $29.6 million and $12.8 million, respectively, and realized no gain or loss on such sales.

The following table summarizes the contractual maturities of our cash equivalents and available-for-sale debt investments as of December 31, 2023:


	Amortized Cost		Fair Value
Within 1 year	$	406,551	$	406,346
After 1 year through 5 years	109,338		109,601

Asset-backed securities	65,478		65,626

Total	$	581,367	$	581,573

Actual maturities can differ from contractual maturities due to various factors including whether the issuers have the right to call or prepay obligations without call or prepayment penalties, and we view our available-for-sale debt investments as available for current operations.

As of December 31, 2023, the amortized cost and fair market value of our held-to-maturity government bonds (Level 1) maturing within a year were $5.2 million. As of December 31, 2022 the amortized cost and fair market value of our held-to-maturity government bonds (Level 1) maturing within a year were $4.4 million and $4.3 million, respectively.