Investments

6 Months Ended

Jun. 30, 2022

2. Investments

Investments consists of available-for-sale securities as follows (in thousands):


	June 30, 2022
	Amortized Cost		Unrealized Gain		Unrealized Loss			Estimated Fair Value
Short-term marketable securities:
Commercial paper	$	44,943	$	—	$	(1	)	$	44,942
U.S. government debt securities		21,518		—		(164	)		21,354
Corporate bonds		24,319		—		(266	)		24,053
Total short-term marketable securities	$	90,780	$	—	$	(431	)	$	90,349
Long-term marketable securities:
U.S. government debt securities	$	—	$	—	$	—		$	—
Corporate bonds		11,874		—		(173	)		11,701
Total long-term marketable securities	$	11,874	$	—	$	(173	)	$	11,701


	December 31, 2021
	Amortized Cost		Unrealized Gain		Unrealized Loss			Estimated Fair Value
Short-term marketable securities:
Commercial paper	$	54,363	$	—	$	(1	)	$	54,362
Corporate bonds		35,231		—		(35	)		35,196
Total short-term marketable securities	$	89,594	$	—	$	(36	)	$	89,558
Long-term marketable securities:
U.S. government debt securities	$	3,996	$	—	$	(17	)	$	3,979
Corporate bonds		21,010		—		(70	)		20,940
Total long-term marketable securities	$	25,006	$	—	$	(87	)	$	24,919

All the commercial paper, U.S. government debt securities, and corporate bonds designated as short-term marketable securities have a contractual maturity date that is equal to or less than one year from the respective balance sheet date. Those that are designated as long-term marketable securities have a contractual maturity date that is more than one year from the respective balance sheet date.

Accrued interest receivable is excluded from the amortized cost and estimated fair value of the Company's marketable securities. Accrued interest receivable of $0.2 million and $0.5 million is presented separately within the prepaid expenses and other current assets line items in the Company's unaudited condensed consolidated balance sheet as of June 30, 2022 and December 31, 2021, respectively.

Investments in a continual unrealized loss position for less than 12 months consist of the following (in thousands):


	June 30, 2022		December 31, 2021
	Fair Value		Fair Value
Corporate bonds	$	35,753	$	60,114
U.S. Government debt securities		21,354		—
Commercial Paper		3,999		3,995
Total available-for-sale securities	$	61,106	$	64,109

There were no investments in a continual unrealized loss position for greater than twelve months.

As of June 30, 2022, the Company did not intend, nor was the Company more likely than not to be required, to sell its available-for-sale investments before the recovery of the amortized cost basis, which may be maturity. Therefore, the Company believes it is more likely than not that its marketable securities in an unrealized loss position will be held until maturity or the recovery of the cost basis of the investment. Based on the Company's assessment, it concluded that none of the available-for-sale investments held as of June 30, 2022 were considered to be impaired, as such, no impairment loss related to other-than-temporary declines in market value was recorded for the three and six months ended June 30, 2022 or as of December 31, 2021. There was no realized gain or loss on available-for-sale securities in the periods presented.