Note 7 - Available-for-Sale Securities - Summary of Company's Available-for-sale Securities Measured at Fair Value on Recurring Basis (Details) - USD ($) $ in Thousands	6 Months Ended	12 Months Ended
Jun. 30, 2026	Dec. 31, 2025
Debt Securities, Available-for-Sale [Line Items]
Available-for-Sale Securities, Amortized Cost	$ 188,609	$ 114,000
Available-for-Sale Securities, Unrealized Gains	8	112
Available-for-Sale Securities, Unrealized Losses	(229)	(4)
Available-for-Sale Securities, Estimated Fair Value	$ 188,388	$ 114,108
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 one year
Available-for-Sale Securities, Amortized Cost	$ 66,898	$ 29,973
Available-for-Sale Securities, Unrealized Gains	0	37
Available-for-Sale Securities, Unrealized Losses	(94)	0
Available-for-Sale Securities, Estimated Fair Value	$ 66,804	$ 30,010
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	$ 48,389	$ 19,484
Available-for-Sale Securities, Unrealized Gains	0	15
Available-for-Sale Securities, Unrealized Losses	(69)	0
Available-for-Sale Securities, Estimated Fair Value	$ 48,320	$ 19,499
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	$ 70,318	$ 56,909
Available-for-Sale Securities, Unrealized Gains	1	52
Available-for-Sale Securities, Unrealized Losses	(61)	(1)
Available-for-Sale Securities, Estimated Fair Value	$ 70,258	$ 56,960
Asset-backed Securities [Member]
Debt Securities, Available-for-Sale [Line Items]
Available-for-Sale Securities , Maturities	Within three years	Within four years
Available-for-Sale Securities, Amortized Cost	$ 3,004	$ 5,914
Available-for-Sale Securities, Unrealized Gains	7	7
Available-for-Sale Securities, Unrealized Losses	(5)	(3)
Available-for-Sale Securities, Estimated Fair Value	$ 3,006	$ 5,918

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