INVESTMENT SECURITIES (Tables)

9 Months Ended

Sep. 30, 2021

INVESTMENT SECURITIES

Schedule of held-to-maturity securities

The following table summarize our investment securities at September 30, 2021 and December 31, 2020:

	September 30, 2021
	Amortized		Gross		Gross
	cost, as		unrealized		unrealized		Estimated
(in thousands)	adjusted		holding gains		holding losses		fair value
Short-term investments:
Obligations of domestic governmental agencies (maturing between October 2021 and April 2022) (held-to-maturity)	$	30,338	$	3	$	1	$	30,340
Long-term investments:
Obligations of domestic governmental agencies (maturing between February 2023 and June 2023) (held-to-maturity)		24,550		1		12		24,539
Total short-term and long-term investment securities	$	54,888	$	4	$	13	$	54,879
	December 31, 2020
	Amortized		Gross		Gross
	cost, as		unrealized		unrealized		Estimated fair
	adjusted		holding gains		holding losses		value
Short-term investments:
Obligations of domestic governmental agencies (maturing between January 2021 and December 2021) (held-to-maturity)	$	51,987	$	1	$	4	$	51,984
Total short-term investment securities	$	51,987	$	1	$	4	$	51,984