CASH, CASH EQUIVALENTS AND SHORT-TERM INVESTMENTS

3 Months Ended

Mar. 31, 2023

Cash, Cash Equivalents, and Short-Term Investments [Abstract]

Cash, cash equivalents and short-term investments

CASH, CASH EQUIVALENTS AND SHORT-TERM INVESTMENTS

Cash equivalents include items almost as liquid as cash, with maturity periods of three months or less when purchased, and short-term investments include items with maturity dates between three months and one year when purchased. As of March 31, 2023 and December 31, 2022, the Company’s cash and cash equivalents and short-term investments were composed of:

	March 31, 2023
	Unaudited
	Fair value level	Adjusted cost basis		Unrealized gains		Unrealized losses		Fair market value		Recorded basis		Cash and cash equivalents		Short-term investments
Cash		$	11,602	$	—	$	—	$	11,602	$	11,602	$	11,602	$	—
Money market funds	Level 1	132,636		—		—		132,636		132,636		132,636		—
Certificate of deposits and term deposits	Level 2	295,804		—		—		295,804		295,804		2,000		293,804
HTM securities (1)
U.S. Treasury bills	Level 1	$	166,659	$	8	$	(272)	166,395		166,659		$	—	$	166,659
Government and governmental agencies	Level 2	$	26,512	$	95	$	(9)	26,598		26,512		$	—	$	26,512
Corporate debt securities	Level 2	$	324,822	$	1,570	$	(1,186)	325,206		324,822		$	39,725	$	285,097
		$	517,993	$	1,673	$	(1,467)	$	518,199	$	517,993	$	39,725	$	478,268
Total		$	958,035	$	1,673	$	(1,467)	$	958,241	$	958,035	$	185,963	$	772,072

	December 31, 2022
	Audited
	Fair value level	Adjusted cost basis		Unrealized gains		Unrealized losses		Fair market value		Recorded basis		Cash and cash equivalents		Short-term investments
Cash		$	9,697	$	—	$	—	$	9,697	$	9,697	$	9,697	$	—
Money market funds	Level 1	105,629		—		—		105,629		105,629		105,629		—
Certificate of deposits and term deposits	Level 2	316,946		—		—		316,946		316,946		—		316,946
HTM securities (1)
U.S. Treasury bills	Level 1	$	188,030	$	8	$	(540)	187,498		188,030		$	—	$	188,030
Government and governmental agencies	Level 2	$	44,357	$	12	$	(12)	44,357		44,357		$	—	$	44,357
Corporate debt securities	Level 2	$	304,766	$	1,066	$	(587)	305,245		304,766		$	—	$	304,766
		$	537,153	$	1,086	$	(1,139)	$	537,100	$	537,153	$	—	$	537,153
Total		$	969,425	$	1,086	$	(1,139)	$	969,372	$	969,425	$	115,326	$	854,099

(1) Changes in fair value of held-to-maturity ("HTM") securities are presented for disclosure purposes as required by ASC 320 and are recorded as finance expenses only if the unrealized loss is identified as a credit loss.

In November 2022, the Company transferred all of its available-for-sale portfolio to HTM as part of the Company's investment strategy. Such transfers are made at fair value at the date of transfer. The net unrealized loss on these securities at the date of transfer was $911. These securities continue to be reported in accumulated comprehensive income (loss) and are amortized over the remaining lives of the securities as an adjustment to the yield. As of March 31, 2023 and December 31, 2022, the unamortized unrealized loss balances were $88 and $445, respectively, and are reported in accumulated other comprehensive income (loss).

In accordance with ASC No. 820, the Company measures its money market funds at fair value. The fair value of the money market funds and HTM securities, which is presented for disclosure purposes, are classified within Level 1 or Level 2. This is because these assets are valued using quoted market prices or alternative pricing sources and models utilizing market observable inputs.

As of March 31, 2023 and December 31, 2022, all investments mature in one year or less.

Unrealized losses from debt securities are primarily attributable to changes in interest rates. The Company does not believe any remaining unrealized losses represent impairments based on the evaluation of available evidence.

Debt securities with continuous unrealized losses for less than 12 months and their related fair values were as follows:

	March 31, 2023		December 31, 2022
	Unaudited		Audited
	Less than 12 months		Less than 12 months
	Fair value	Unrealized loss	Fair value	Unrealized loss
U.S. Treasury bills	116,323	(272)	162,813	(540)
Government and governmental agencies	1,597	(9)	38,477	(12)
Corporate debt securities	224,483	(1,186)	162,085	(587)
Total	342,403	(1,467)	363,375	(1,139)

As of March 31, 2023, no continuous unrealized losses for 12 months or greater was identified.