Short-term Investments

12 Months Ended

Dec. 31, 2022

Investments, Debt and Equity Securities [Abstract]

Short-term investments consisted of available-for-sale and equity securities as follows (in thousands):


Type of securities as of December 31, 2022	Amortized cost		Gross unrealized gains		Gross unrealized losses		Fair value
Corporate debt securities	$	62,862	$	—	$	(359)	$	62,503
U.S. government-related debt securities	22,009		—		(230)		21,779
Total available-for-sale debt securities	$	84,871	$	—	$	(589)	$	84,282


Type of securities as of December 31, 2021	Amortized cost		Gross unrealized gains		Gross unrealized losses		Fair value
Corporate debt securities	$	177,375	$	3	$	(195)	$	177,183
U.S. government-related debt securities	33,134		2		(97)		33,039
Asset-backed securities	31,631		—		(32)		31,599
Total available-for-sale debt securities	$	242,140	$	5	$	(324)	$	241,821

The fair values of available-for-sale debt securities by contractual maturity at December 31 were as follows (in thousands):


	2022		2021
Maturing in one year or less	$	81,004	$	174,534
Maturing in one to three years	3,278		67,287
Total available-for-sale debt securities	$	84,282	$	241,821

The Company has both the intent and ability to sell its available-for-sale debt securities maturing greater than one year within 12 months from the balance sheet date and, accordingly, has classified these securities as current in the consolidated balance sheets.

The following table summarizes investments that have been in a continuous unrealized loss position as of December 31, 2022 (in thousands).


	Less than 12 months				12 months or greater				Total
	Fair Value		Gross unrealized losses		Fair Value		Gross unrealized losses		Fair Value		Gross unrealized losses
Corporate debt securities	$	10,232	$	(52)	$	48,271	$	(307)	$	58,503	$	(359)
U.S. government-related debt securities	3,988		(16)		17,790		(214)		21,778		(230)
Total	$	14,220	$	(68)	$	66,061	$	(521)	$	80,281	$	(589)

The Company invests in securities that are rated investment grade or better. The unrealized losses on available-for-sale debt securities as of December 31, 2022 were caused primarily by interest rate increases.

The Company reviews the individual securities in its portfolio for impairment when events indicate the fair value of the investments may be below the carrying value. The Company reviews the individual securities in its portfolio for indications that unrealized losses are credit related and require an allowance to be recorded at the present value of the future expected cash flows. The Company determined unrealized losses were not for credit losses and so did not record an allowance related to its available-for-sale debt investments for the year ended December 31, 2022. The Company did not record any impairment charges related to its available-for-sale debt investments for the year ended December 31, 2022.