Note 7 - Investments - Summary of Marketable Securities (Details) - USD ($) $ in Thousands	Sep. 30, 2025	Dec. 31, 2024
Cash equivalents	$ 90,039	$ 171,987
Amortized cost basis	37,349
Unrealized gains	26
Unrealized losses	(1)
Fair value	37,374
Unrealized gains	26
Total assets at fair value	63,790
Total assets at fair value, unrealized gains	26
Total assets at fair value, unrealized losses	(3)
Total assets at fair value, fair value	63,813
US Government Agencies Debt Securities [Member]
Amortized cost basis	24,025
Unrealized gains	0
Unrealized losses	(1)
Fair value	24,024
Unrealized gains	0
Corporate Debt Securities [Member]
Amortized cost basis	6,356
Unrealized gains	22
Unrealized losses	0
Fair value	6,378
Unrealized gains	22
Commercial Paper, Not Included with Cash and Cash Equivalents [Member]
Amortized cost basis	2,879
Unrealized gains	2
Unrealized losses	0
Fair value	2,881
Unrealized gains	2
Certificates of Deposit [Member]
Amortized cost basis	4,089
Unrealized gains	2
Unrealized losses	0
Fair value	4,091
Unrealized gains	2
Money Market Funds [Member]
Cash equivalents	2,569
Cash equivalents, unrealized gains	0
Cash equivalents, unrealized loss	0
Cash equivalents, fair value	2,569
US Government Corporations and Agencies Securities [Member]
Cash equivalents	11,305
Cash equivalents, unrealized gains	0
Cash equivalents, unrealized loss	(1)
Cash equivalents, fair value	11,304
Commercial Paper [Member]
Cash equivalents	12,567
Cash equivalents, unrealized gains	0
Cash equivalents, unrealized loss	(1)
Cash equivalents, fair value	12,566
Cash Equivalents [Member]
Cash equivalents	26,441
Cash equivalents, unrealized gains	0
Cash equivalents, unrealized loss	(2)
Cash equivalents, fair value	$ 26,439

Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) on cash and cash equivalents.

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