Note 9 - Cash, Cash Equivalents, Investments and Restricted Cash

3 Months Ended

Mar. 31, 2023

Notes to Financial Statements

Financial Instruments Disclosure [Text Block]

9. CASH, CASH EQUIVALENTS, INVESTMENTS AND RESTRICTED CASH

The following is a summary of the Company’s cash, cash equivalents and debt investments (in thousands): 

	March 31,		December 31,
	2023		2022
Cash	$	447,746	$	273,145
Money market funds		41,226		15,462
Certificates of deposit		131,042		130,467
Corporate debt securities		244,155		292,586
Commercial paper		18,163		17,928
U.S. treasuries and government agency bonds		35,238		8,285
Auction-rate securities backed by student-loan notes		1,516		1,711
Total	$	919,086	$	739,584

	March 31,		December 31,
	2023		2022
Reported as:
Cash and cash equivalents	$	488,972	$	288,607
Short-term investments		428,598		449,266
Investment within other long-term assets		1,516		1,711
Total	$	919,086	$	739,584

The following table summarizes the contractual maturities of the short-term and long-term available-for-sale investments as of March 31, 2023 (in thousands):  

	Amortized Cost		Fair Value
Due in less than 1 year	$	252,449	$	249,803
Due in 1 - 5 years		181,774		178,795
Due in greater than 5 years		1,571		1,516
Total	$	435,794	$	430,114

Gross realized gains and losses recognized on the sales of available-for-sale investments were not material for the periods presented. 

The following tables summarize the unrealized gain and loss positions related to the available-for-sale investments (in thousands):  

	March 31, 2023
	Amortized Cost		Unrealized Gains		Unrealized Losses			Fair Value
Money market funds	$	41,226	$	-	$	-		$	41,226
Certificates of deposit		131,042		-		-			131,042
Corporate debt securities		249,743		39		(5,627	)		244,155
Commercial paper		18,163		-		-			18,163
U.S. treasuries and government agency bonds		35,276		83		(121	)		35,238
Auction-rate securities backed by student-loan notes		1,570		-		(54	)		1,516
Total	$	477,020	$	122	$	(5,802	)	$	471,340

	December 31, 2022
	Amortized Cost		Unrealized Gains		Unrealized Losses			Fair Value
Money market funds	$	15,462	$	-	$	-		$	15,462
Certificates of deposit		130,467		-		-			130,467
Corporate debt securities		300,529		18		(7,961	)		292,586
Commercial paper		17,928		-		-			17,928
U.S. treasuries and government agency bonds		8,487		-		(202	)		8,285
Auction-rate securities backed by student-loan notes		1,770		-		(59	)		1,711
Total	$	474,643	$	18	$	(8,222	)	$	466,439

The following tables present information about the available-for-sale investments that had been in a continuous unrealized loss position for less than 12 months and for greater than 12 months (in thousands): 

	March 31, 2023
	Less than 12 Months					Greater than 12 Months					Total
	Fair Value		Unrealized Losses			Fair Value		Unrealized Losses			Fair Value		Unrealized Losses
Corporate debt securities	$	18,084	$	(68	)	$	212,767	$	(5,559	)	$	230,851	$	(5,627	)
U.S. treasuries and government agency bonds		2,878		(5	)		7,383		(116	)		10,261		(121	)
Auction-rate securities backed by student-loan notes		-		-			1,516		(54	)		1,516		(54	)
Total	$	20,962	$	(73	)	$	221,666	$	(5,729	)	$	242,628	$	(5,802	)

	December 31, 2022
	Less than 12 Months					Greater than 12 Months					Total
	Fair Value		Unrealized Losses			Fair Value		Unrealized Losses			Fair Value		Unrealized Losses
Corporate debt securities	$	72,943	$	(973	)	$	202,074	$	(6,988	)	$	275,017	$	(7,961	)
U.S. treasuries and government agency bonds		987		(2	)		7,298		(200	)		8,285		(202	)
Auction-rate securities backed by student-loan notes		-		-			1,711		(59	)		1,711		(59	)
Total	$	73,930	$	(975	)	$	211,083	$	(7,247	)	$	285,013	$	(8,222	)

An impairment exists when the fair value of an investment is less than its amortized cost basis. As of March 31, 2023 and December 31, 2022, the Company did not consider the impairment of its investments to be a result of credit losses. The Company typically invests in highly rated securities, with the primary objective of minimizing the potential risk of principal loss. The Company’s investment policy generally requires securities to be investment grade and limits the amount of credit exposure to any one issuer. When evaluating a debt security for impairment, management reviews factors such as the Company’s intent to sell, or whether it will more likely than not be required to sell, the security before recovery of its amortized cost basis, the extent to which the fair value of the security is less than its cost, the financial condition of the issuer and the credit quality of the investment.

The Company’s auction-rate securities are backed by pools of student loans supported by guarantees by the U.S. Department of Education. The underlying maturities of these securities are up to 23 years. The Company has received all scheduled interest payments on a timely basis pursuant to the terms and conditions of the securities. The Company does not intend to sell these securities, and it is more likely than not that the Company will not be required to sell these securities, before recovery of its amortized cost basis. To date, the Company has redeemed $41.7 million, or 96% of the original portfolio in these auction-rate securities, at par without any realized losses.

Non-Marketable Equity Investment

In  November 2020, the Company made an equity investment in a privately held Swiss company (the “Investee”) that is accounted for under the measurement alternative. In April 2022, the Company made an investment of CHF 2.0 million in a convertible loan that will convert into additional shares of the Investee. One member of the Company’s Board of Directors is an executive officer of a company that has a commercial relationship with the Investee. In addition, the Company’s Chief Executive Officer has a personal investment in the Investee and is on the Investee’s board of directors. As of March 31, 2023 and December 31, 2022, the Company’s investment in the Investee, which is denominated in Swiss Francs, had a carrying value of $5.8 million and $5.4 million, respectively. The Company did not record any impairment or adjustments resulting from observable price changes for the three months ended March 31, 2023.

Restricted Cash

The following table provides a reconciliation of cash, cash equivalents and restricted cash reported on the Condensed Consolidated Balance Sheets to the amounts reported on the Condensed Consolidated Statements of Cash Flows (in thousands):   

	March 31,		December 31,
	2023		2022
Cash and cash equivalents	$	488,972	$	288,607
Restricted cash included in other long-term assets		123		122
Total cash, cash equivalents and restricted cash reported on the Condensed Consolidated Statements of Cash Flows	$	489,095	$	288,729

As of March 31, 2023 and December 31, 2022, restricted cash included a security deposit that is set aside in a bank account and cannot be withdrawn by the Company under the terms of a lease agreement. The restriction will end upon the expiration of the lease.