Marketable Securities

12 Months Ended

Dec. 31, 2019

Marketable Securities [Abstract]

Marketable Securities

5. Marketable Securities:

The Company has evaluated its investment policies and determined that all of its marketable securities, which are comprised of debt securities, are to be classified as available-for-sale.  The Company’s available-for-sale debt securities are carried at fair value, with the unrealized gains and losses reported in Stockholders’ equity under the caption “Accumulated other comprehensive loss.”  Realized gains and losses on available-for-sale securities are included in “Other income (expense)” on the Consolidated Statements of Operations. The Company records other-than-temporary impairment charges for its available-for-sale debt securities when it intends to sell the securities, it is more-likely-than not that it will be required to sell the securities before a recovery, or when it does not expect to recover the entire amortized cost basis of the securities.  The cost of securities sold is based on the specific identification method.

The Company has determined that the gross unrealized losses on its marketable securities at December 31, 2019 and 2018 are temporary in nature. The Company reviews its investment portfolio to identify and evaluate marketable securities that have indications of possible impairment. Factors considered in determining whether a loss is other-than-temporary include the length of time and extent to which fair value has been less than the cost basis, credit quality and the Company’s ability and intent to hold the securities for a period of time sufficient to allow for any anticipated recovery in market value.

At December 31, 2019 and 2018, marketable securities are categorized as follows:

	Amortized Cost		Gross Unrealized Holding Gains		Gross Unrealized Holding Losses		Fair Value
December 31, 2019
Municipal notes and bonds	$	80,926	$	188	$	6	$	81,108
Asset-backed securities		10,767		12		—		10,779
Certificates of deposit		30,500		7		—		30,507
Commercial paper		30,707		1		—		30,708
Corporate bonds		36,409		52		—		36,461
Total marketable securities	$	189,309	$	260	$	6	$	189,563
December 31, 2018
Municipal notes and bonds	$	62,681	$	43	$	40	$	62,684
Total marketable securities	$	62,681	$	43	$	40	$	62,684

The amortized cost and estimated fair value of marketable securities classified by the maturity date listed on the security, regardless of the Consolidated Balance Sheet classification, is as follows at December 31, 2019 and 2018:

	December 31, 2019				December 31, 2018
	Amortized Cost		Fair Value		Amortized Cost		Fair Value
Due within one year	$	152,649	$	152,852	$	47,767	$	47,732
Due after one through five years		36,660		36,711		14,914		14,952
Due after five through ten years		—		—		—		—
Due after ten years		—		—		—		—
Total marketable securities	$	189,309	$	189,563	$	62,681	$	62,684

The following table summarizes the estimated fair value and gross unrealized holding losses of marketable securities, aggregated by investment instrument and period of time in an unrealized loss position, at December 31, 2019 and 2018.

	In Unrealized Loss Position For Less Than 12 Months				In Unrealized Loss Position For Greater Than 12 Months
	Fair Value		Gross Unrealized Losses		Fair Value		Gross Unrealized Losses
December 31, 2019
Municipal notes and bonds	$	14,166	$	6	$	—	$	—
Total marketable securities	$	14,166	$	6	$	—	$	—
December 31, 2018
Municipal notes and bonds	$	27,952	$	30	$	4,671	$	10
Total marketable securities	$	27,952	$	30	$	4,671	$	10

See Note 4 for additional discussion regarding the fair value of the Company’s marketable securities.