Marketable Securities

6 Months Ended

Jun. 30, 2020

Investments Debt And Equity Securities [Abstract]

3.	Marketable Securities

The following table summarizes the Company’s available-for-sale marketable securities as of June 30, 2020 and December 31, 2019 at net book value:

	June 30, 2020
	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses			Estimated Fair Value
	(In thousands)
Marketable securities:
U.S. Treasury securities	$	41,487	$	75	$	-		$	41,562
Financial institution debt securities		28,512		80		-			28,592
Corporate debt securities		4,963		-		-			4,963
Total	$	74,962	$	155	$	-		$	75,117

	December 31, 2019
	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses			Estimated Fair Value
	(In thousands)
Marketable securities:
U.S. Treasury securities	$	159,361	$	142	$	(1	)	$	159,502
Financial institution debt securities		40,173		105		-			40,278
Corporate debt securities		18,966		1		-			18,967
Other asset-backed securities		8,485		14		-			8,499
Total	$	226,985	$	262	$	(1	)	$	227,246

The amortized cost of available-for-sale securities is adjusted for amortization of premiums and accretion of discounts to maturity. At June 30, 2020 and December 31, 2019, the balance in the Company’s accumulated other comprehensive income was composed of activity related to the Company’s available-for-sale marketable securities. There were no material realized gains or losses in the six months ended June 30, 2020 or for the year ended December 31, 2019 and, as a result, the Company did not reclassify any amounts out of accumulated other comprehensive income during the period. The Company did not have any securities in a material unrealized loss position at June 30, 2020.

The Company's available-for-sale securities that are classified as short-term marketable securities in the condensed consolidated balance sheet mature within one year or less as of the balance sheet date. Available-for-sale securities that are classified as noncurrent in the condensed consolidated balance sheet are those that mature after one year but within five years from the balance sheet date and that the Company does not intend to dispose of within the next twelve months. At June 30, 2020 and December 31, 2019, the Company did not hold any investments that matured beyond five years of the balance sheet date.