INVESTMENT SECURITIES (Tables)

12 Months Ended

Dec. 31, 2022

INVESTMENT SECURITIES

Schedule of investment securities

The following tables summarize our investment securities at December 31, 2022 and 2021:

	December 31, 2022
	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 January 2023 and December 2023) (held-to-maturity)	$	59,374	$		$	1,053	$	58,321
Long-term investments:
Obligations of domestic governmental agencies (maturing between January 2024 and February 2024) (held-to-maturity)		12,404				429		11,975
Total short-term and long-term investment securities	$	71,778	$	—	$	1,482	$	70,296
	December 31, 2021
	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 2022 and April 2022) (held-to-maturity)	$	15,876	$	—	$	4	$	15,872
Long-term investments:
Obligations of domestic governmental agencies (maturing between February 2023 and June 2023) (held-to-maturity)		35,533				160		35,373
Total short-term and long-term investment securities	$	51,409	$	—	$	164	$	51,245