Investments

6 Months Ended

Jun. 30, 2023

Investments, Debt and Equity Securities [Abstract]

Investments

4. INVESTMENTS

Investments consisted of the following (in thousands):

			Gross Unrealized
					Losses
	Amortized				Less than			Greater than			Estimated
June 30, 2023	Cost		Gains		One Year			One Year			Fair Value
Short-term investments:
Available-for-sale securities:
Corporate debt securities	$	77,279	$	—	$	(82	)	$	(1,106	)	$	76,091
U.S. government and agency debt securities		73,188		1		(116	)		(991	)		72,082
Non-U.S. government debt securities		15,359		—		—			(278	)		15,081
Total short-term investments		165,826		1		(198	)		(2,375	)		163,254
Long-term investments:
Available-for-sale securities:
Corporate debt securities		38,825		—		(529	)		(765	)		37,531
U.S. government and agency debt securities		40,219		—		(463	)		(980	)		38,776
		79,044		—		(992	)		(1,745	)		76,307
Held-to-maturity securities:
Certificates of deposit		1,820		—		—			—			1,820
Total long-term investments		80,864		—		(992	)		(1,745	)		78,127
Total investments	$	246,690	$	1	$	(1,190	)	$	(4,120	)	$	241,381
December 31, 2022
Short-term investments:
Available-for-sale securities:
Corporate debt securities	$	141,418	$	—	$	(424	)	$	(2,054	)	$	138,940
U.S. government and agency debt securities		143,710		16		(266	)		(1,289	)		142,171
Non-U.S. government debt securities		35,455		—		(28	)		(546	)		34,881
Total short-term investments		320,583		16		(718	)		(3,889	)		315,992
Long-term investments:
Available-for-sale securities:
Corporate debt securities		68,229		—		(1,550	)		(676	)		66,003
U.S. government and agency debt securities		62,220		—		(917	)		(1,424	)		59,879
Non-U.S. government debt securities		4,099		—		—			(191	)		3,908
		134,548		—		(2,467	)		(2,291	)		129,790
Held-to-maturity securities:
Certificates of deposit		1,820		—		—			—			1,820
Total long-term investments		136,368		—		(2,467	)		(2,291	)		131,610
Total investments	$	456,951	$	16	$	(3,185	)	$	(6,180	)	$	447,602

At June 30, 2023, the Company reviewed its investment portfolio to assess whether the unrealized losses on its available-for-sale investments were temporary. Investments with unrealized losses consisted primarily of corporate debt securities and debt securities issued and backed by U.S. agencies and the U.S. government. At June 30, 2023, 156 of the Company’s 163 investment securities were in an unrealized loss position and had an aggregate estimated fair value of $231.1 million. Approximately 46% of the Company’s investment securities at June 30, 2023 are in each of corporate debt securities, with a minimum rating of A2 (Moody’s)/A (Standard and Poor’s), and debt securities issued by the U.S. government or its agencies. In a rising interest rate environment, the Company expects its fixed-rate investment securities will carry unrealized losses. In making the determination whether the decline in fair value of these securities was temporary, the Company evaluated whether it intended to sell the security and whether it was more likely than not that the Company would be required to sell the security before recovering its amortized cost basis. The Company has the intent and ability to hold these investments until recovery, which may be at maturity.

Realized gains and losses on the sales and maturities of investments, which were identified using the specific identification method, were as follows:

	Six Months Ended June 30,
(In thousands)	2023		2022
Proceeds from the sales and maturities of investments	$	240,544	$	109,925
Realized gains	$	—	$	—
Realized losses	$	—	$	—

The Company’s available-for-sale and held-to-maturity securities at June 30, 2023 had contractual maturities in the following periods:

	Available-for-sale				Held-to-maturity
	Amortized		Estimated		Amortized		Estimated
(In thousands)	Cost		Fair Value		Cost		Fair Value
Within 1 year	$	165,826	$	163,254	$	1,820	$	1,820
After 1 year through 5 years		79,044		76,307		—		—
Total	$	244,870	$	239,561	$	1,820	$	1,820