Note 4 - Fair Value Measurements - Assets and Liabilities Measured at Fair Value on Recurring Basis (Details) - USD ($) $ in Thousands	Dec. 31, 2024	Dec. 31, 2023
Securities, fair value	$ 182,817	$ 109,664
Securities, fair value	(182,817)	(109,664)
US Government Agencies Debt Securities [Member]
Securities, fair value	57,155	18,894
Securities, fair value	(57,155)	(18,894)
Certificates of Deposit [Member]
Securities, fair value	8,524	5,245
Securities, fair value	(8,524)	(5,245)
Corporate Debt Securities [Member]
Securities, fair value	80,822	52,369
Securities, fair value	(80,822)	(52,369)
Commercial Paper, Not Included with Cash and Cash Equivalents [Member]
Securities, fair value	22,275	28,126
Securities, fair value	(22,275)	(28,126)
Debt Security, Government, Non-US [Member]
Securities, fair value	2,146	2,448
Securities, fair value	(2,146)	(2,448)
Asset-Backed Securities [Member]
Securities, fair value	11,895	2,582
Securities, fair value	(11,895)	(2,582)
Fair Value, Recurring [Member]
Cash equivalents	21,042	14,646
Total financial assets	203,859	124,310
Total financial assets	203,859	124,310
Preferred stock warrant liability		(110)
Fair Value, Recurring [Member] \| US Government Agencies Debt Securities [Member]
Securities, fair value	57,155	18,894
Securities, fair value	(57,155)	(18,894)
Fair Value, Recurring [Member] \| Certificates of Deposit [Member]
Securities, fair value	8,524	5,245
Securities, fair value	(8,524)	(5,245)
Fair Value, Recurring [Member] \| Corporate Debt Securities [Member]
Securities, fair value	80,822	52,369
Securities, fair value	(80,822)	(52,369)
Fair Value, Recurring [Member] \| Commercial Paper, Not Included with Cash and Cash Equivalents [Member]
Securities, fair value	22,275	28,126
Securities, fair value	(22,275)	(28,126)
Fair Value, Recurring [Member] \| Debt Security, Government, Non-US [Member]
Securities, fair value	2,146	2,448
Securities, fair value	(2,146)	(2,448)
Fair Value, Recurring [Member] \| Asset-Backed Securities [Member]
Securities, fair value	11,895	2,582
Securities, fair value	(11,895)	(2,582)
Fair Value, Recurring [Member] \| Fair Value, Inputs, Level 1 [Member]
Cash equivalents	21,042	14,646
Total financial assets	78,197	31,006
Total financial assets	78,197	31,006
Preferred stock warrant liability		0
Fair Value, Recurring [Member] \| Fair Value, Inputs, Level 1 [Member] \| US Government Agencies Debt Securities [Member]
Securities, fair value	57,155	16,360
Securities, fair value	(57,155)	(16,360)
Fair Value, Recurring [Member] \| Fair Value, Inputs, Level 1 [Member] \| Certificates of Deposit [Member]
Securities, fair value	0	0
Securities, fair value	0	0
Fair Value, Recurring [Member] \| Fair Value, Inputs, Level 1 [Member] \| Corporate Debt Securities [Member]
Securities, fair value	0	0
Securities, fair value	0	0
Fair Value, Recurring [Member] \| Fair Value, Inputs, Level 1 [Member] \| Commercial Paper, Not Included with Cash and Cash Equivalents [Member]
Securities, fair value	0	0
Securities, fair value	0	0
Fair Value, Recurring [Member] \| Fair Value, Inputs, Level 1 [Member] \| Debt Security, Government, Non-US [Member]
Securities, fair value	0	0
Securities, fair value	0	0
Fair Value, Recurring [Member] \| Fair Value, Inputs, Level 1 [Member] \| Asset-Backed Securities [Member]
Securities, fair value	0	0
Securities, fair value	0	0
Fair Value, Recurring [Member] \| Fair Value, Inputs, Level 2 [Member]
Cash equivalents	0	0
Total financial assets	125,662	93,304
Total financial assets	125,662	93,304
Preferred stock warrant liability		0
Fair Value, Recurring [Member] \| Fair Value, Inputs, Level 2 [Member] \| US Government Agencies Debt Securities [Member]
Securities, fair value	0	2,534
Securities, fair value	0	(2,534)
Fair Value, Recurring [Member] \| Fair Value, Inputs, Level 2 [Member] \| Certificates of Deposit [Member]
Securities, fair value	8,524	5,245
Securities, fair value	(8,524)	(5,245)
Fair Value, Recurring [Member] \| Fair Value, Inputs, Level 2 [Member] \| Corporate Debt Securities [Member]
Securities, fair value	80,822	52,369
Securities, fair value	(80,822)	(52,369)
Fair Value, Recurring [Member] \| Fair Value, Inputs, Level 2 [Member] \| Commercial Paper, Not Included with Cash and Cash Equivalents [Member]
Securities, fair value	22,275	28,126
Securities, fair value	(22,275)	(28,126)
Fair Value, Recurring [Member] \| Fair Value, Inputs, Level 2 [Member] \| Debt Security, Government, Non-US [Member]
Securities, fair value	2,146	2,448
Securities, fair value	(2,146)	(2,448)
Fair Value, Recurring [Member] \| Fair Value, Inputs, Level 2 [Member] \| Asset-Backed Securities [Member]
Securities, fair value	11,895	2,582
Securities, fair value	(11,895)	(2,582)
Fair Value, Recurring [Member] \| Fair Value, Inputs, Level 3 [Member]
Cash equivalents	0	0
Total financial assets	0	0
Total financial assets	0	0
Preferred stock warrant liability		(110)
Fair Value, Recurring [Member] \| Fair Value, Inputs, Level 3 [Member] \| US Government Agencies Debt Securities [Member]
Securities, fair value	0	0
Securities, fair value	0	0
Fair Value, Recurring [Member] \| Fair Value, Inputs, Level 3 [Member] \| Certificates of Deposit [Member]
Securities, fair value	0	0
Securities, fair value	0	0
Fair Value, Recurring [Member] \| Fair Value, Inputs, Level 3 [Member] \| Corporate Debt Securities [Member]
Securities, fair value	0	0
Securities, fair value	0	0
Fair Value, Recurring [Member] \| Fair Value, Inputs, Level 3 [Member] \| Commercial Paper, Not Included with Cash and Cash Equivalents [Member]
Securities, fair value	0	0
Securities, fair value	0	0
Fair Value, Recurring [Member] \| Fair Value, Inputs, Level 3 [Member] \| Debt Security, Government, Non-US [Member]
Securities, fair value	0	0
Securities, fair value	0	0
Fair Value, Recurring [Member] \| Fair Value, Inputs, Level 3 [Member] \| Asset-Backed Securities [Member]
Securities, fair value	0	0
Securities, fair value	$ 0	$ 0

Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amount of short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Excludes cash and cash equivalents within disposal group and discontinued operation.

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Fair value of asset after deduction of liability.

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Value of outstanding derivative securities that permit the holder the right to purchase securities (usually equity) from the issuer at a specified price.

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