3. Available-for-Sale Marketable Securities

As of June 30, 2023 and December 31, 2022, the Company’s available-for-sale marketable securities consisted of debt securities issued by U.S. government-sponsored entities and investment grade institutions as well as municipal bonds.

The following tables summarize the Company’s available-for-sale marketable securities by major type of security as of June 30, 2023 and December 31, 2022:

As of June 30, 2023

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As of December 31, 2022

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The following tables summarize the fair value and gross unrealized losses of the Company’s available-for-sale marketable securities by investment category and disaggregated by the length of time that individual debt securities have been in a continuous unrealized loss position as of June 30, 2023 and December 31, 2022:

As of June 30, 2023

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As of December 31, 2022

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As of June 30, 2023 and December 31, 2022, no allowance for credit losses were recognized on the Company’s available-for-sale debt securities as no portion of the unrealized losses associated with those securities were due to credit losses. The information that the Company considered in reaching the conclusion that an allowance for credit losses was not necessary is as follows:

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As of June 30, 2023 and December 31, 2022, the Company held a total of 17 out of 22 positions and 35 out of 39 positions, respectively, that were in an unrealized loss position, all of which had been in an unrealized loss position for 12 months or greater as of June 30, 2023. Unrealized losses individually and in aggregate, including any in an unrealized loss position for 12 months or greater, were not considered to be material for each respective period. Based on the Company’s review of these securities, the Company believes that the cost basis of its available-for-sale marketable securities is recoverable.

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U.S. government agency obligations. The unrealized losses on the Company’s investments in direct obligations of government agencies were due to changes in interest rates and non-credit related factors. The credit ratings of these investments in the Company’s portfolio have not been downgraded below investment grade status. The contractual terms of these investments do not permit the issuer to repay principal at a price less than the amortized cost bases of the investments, which is equivalent to the par value on the maturity date. The Company expects to recover the entire amortized cost bases of these securities on the maturity date. The Company does not intend to sell these investments, and it is not “more likely than not” that the Company will be required to sell these investments before recovery of their amortized cost bases. The Company held 3 out of 3 positions for its U.S. government agency obligations, that were in unrealized loss positions as of June 30, 2023.

Corporate bonds and municipal bonds. The unrealized losses on the Company’s investments in corporate bonds and municipal bonds were due to changes in interest rates and non-credit related factors. The credit ratings of these investments in the Company’s portfolio have not been downgraded below investment grade status. The contractual terms of these investments do not permit the issuer to repay principal at a price less than the amortized cost bases of the investments, which is equivalent to the par value on the maturity date. The Company expects to recover the entire amortized cost bases of these securities on the maturity date. The Company does not intend to sell these investments, and it is not “more likely than not” that the Company will be required to sell these investments before recovery of their amortized cost bases. The Company held 8 out of 8 positions for its corporate bonds, and 6 out of 11 positions for its municipal bonds, that were in unrealized loss positions as of June 30, 2023.

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The Company classifies its marketable debt securities based on their contractual maturity dates. As of June 30, 2023, the Company’s marketable debt securities mature at various dates through November 2024. The amortized cost and fair values of marketable debt securities by contractual maturity were as follows:

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All available-for-sale marketable securities are classified as marketable securities, current or marketable securities, non-current depending on the contractual maturity date of the individual available-for-sale security. Other income, net includes interest and dividends, accretion/amortization of discounts/premiums, realized gains and losses on sales of securities and credit loss expense due to declines in the fair value of securities, if any. The cost of securities sold is based on the specific identification method.

There were no sales of available-for-sale marketable securities during each of the three and six months ended June 30, 2023 and 2022.

As of June 30, 2023 and December 31, 2022, accrued interest receivables on the Company’s available-for-sale debt securities were $420 and $489, respectively, and were included within other receivables.