Note 9 - Cash, Cash Equivalents, Investments and Restricted Cash (Tables)

9 Months Ended

Sep. 30, 2025

Notes Tables

Fair Value, by Balance Sheet Grouping [Table Text Block]

	September 30,		December 31,
	2025		2024
Cash	$	580,992	$	679,949
Money market funds		500,259		11,867
Certificates of deposit		154,489		164,418
U.S. treasuries and government agency bonds		33,249		-
Auction-rate securities backed by student-loan notes		74		148
Corporate debt securities		-		6,712
Total	$	1,269,063	$	863,094

	September 30,		December 31,
	2025		2024
Reported as:
Cash and cash equivalents	$	1,081,251	$	691,816
Investment within short-term investments		187,738		171,130
Investment within other long-term assets		74		148
Total	$	1,269,063	$	863,094

Investments Classified by Contractual Maturity Date [Table Text Block]

	Amortized Cost		Fair Value
Due in less than 1 year	$	89,419	$	89,427
Due in 1 - 5 years		98,311		98,311
Due in greater than 5 years		75		74
Total	$	187,805	$	187,812

Unrealized Gain (Loss) on Investments [Table Text Block]

	September 30, 2025
	Amortized Cost		Unrealized Gains		Unrealized Losses			Fair Value
Money market funds	$	500,259	$	-	$	-		$	500,259
Certificates of deposit		154,489		-		-			154,489
U.S. treasuries and government agency bonds		33,241		8		-			33,249
Auction-rate securities backed by student-loan notes		75		-		(1	)		74
Total	$	688,064	$	8	$	(1	)	$	688,071

	December 31, 2024
	Amortized Cost		Unrealized Losses			Fair Value
Money market funds	$	11,867	$	-		$	11,867
Certificates of deposit		164,418		-			164,418
Corporate debt securities		6,779		(67	)		6,712
Auction-rate securities backed by student-loan notes		150		(2	)		148
Total	$	183,214	$	(69	)	$	183,145

Debt Securities, Available-for-Sale, Unrealized Loss Position, Fair Value [Table Text Block]

	September 30, 2025
	Greater than 12 Months
	Fair Value		Unrealized Losses
Auction-rate securities backed by student-loan notes	$	74	$	(1	)
Total	$	74	$	(1	)

	December 31, 2024
	Greater than 12 Months
	Fair Value		Unrealized Losses
Corporate debt securities	$	6,712	$	(67	)
Auction-rate securities backed by student-loan notes		148		(2	)
Total	$	6,860	$	(69	)

Restrictions on Cash and Cash Equivalents [Table Text Block]

	September 30,		December 31,
	2025		2024
Cash and cash equivalents	$	1,081,251	$	691,816
Restricted cash included in other long-term assets		142		125
Total cash, cash equivalents and restricted cash reported on the Condensed Consolidated Statements of Cash Flows	$	1,081,393	$	691,941