Note 8 - Available-for-sale Securities - Summary of Company's Available-for-sale Securities Measured at Fair Value on Recurring Basis (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2025	Dec. 31, 2024
Debt Securities, Available-for-Sale [Line Items]
Available-for-Sale Securities, Amortized Cost	$ 114,000	$ 165,387
Available-for-Sale Securities, Unrealized Gains	112	22
Available-for-Sale Securities, Unrealized Losses	(4)	(73)
Available-for-Sale Securities, Estimated Fair Value	$ 114,108	$ 165,336
Securities of U.S. Government and Government Agencies [Member]
Debt Securities, Available-for-Sale [Line Items]
Available-for-Sale Securities , Maturities	Within one year	Within two years
Available-for-Sale Securities, Amortized Cost	$ 29,973	$ 51,500
Available-for-Sale Securities, Unrealized Gains	37	13
Available-for-Sale Securities, Unrealized Losses	0	(13)
Available-for-Sale Securities, Estimated Fair Value	$ 30,010	$ 51,500
Commercial Paper [Member]
Debt Securities, Available-for-Sale [Line Items]
Available-for-Sale Securities , Maturities	Within one year	Within one year
Available-for-Sale Securities, Amortized Cost	$ 19,484	$ 44,480
Available-for-Sale Securities, Unrealized Gains	15	7
Available-for-Sale Securities, Unrealized Losses	0	(14)
Available-for-Sale Securities, Estimated Fair Value	$ 19,499	$ 44,473
Certificates of Deposit [Member]
Debt Securities, Available-for-Sale [Line Items]
Available-for-Sale Securities , Maturities	Within one year
Available-for-Sale Securities, Amortized Cost	$ 1,720
Available-for-Sale Securities, Unrealized Gains	1
Available-for-Sale Securities, Unrealized Losses	0
Available-for-Sale Securities, Estimated Fair Value	$ 1,721
Corporate Debt Securities [Member]
Debt Securities, Available-for-Sale [Line Items]
Available-for-Sale Securities , Maturities	Within one year	Within one year
Available-for-Sale Securities, Amortized Cost	$ 56,909	$ 64,615
Available-for-Sale Securities, Unrealized Gains	52	1
Available-for-Sale Securities, Unrealized Losses	(1)	(46)
Available-for-Sale Securities, Estimated Fair Value	$ 56,960	$ 64,570
Asset-backed Securities [Member]
Debt Securities, Available-for-Sale [Line Items]
Available-for-Sale Securities , Maturities	Within four years	Within four years
Available-for-Sale Securities, Amortized Cost	$ 5,914	$ 4,792
Available-for-Sale Securities, Unrealized Gains	7	1
Available-for-Sale Securities, Unrealized Losses	(3)
Available-for-Sale Securities, Estimated Fair Value	$ 5,918	$ 4,793

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