Note 2 - Investments and Fair Value Measurements - Schedule of Cash, Cash Equivalents, and Investments (Details) - USD ($)	Jun. 30, 2025	Dec. 31, 2024
Cash, restricted cash and cash equivalents, amortized cost	$ 35,107,000	$ 33,811,000
Cash, restricted cash and cash equivalents	0	0
Cash, restricted cash and cash equivalents	0	0
Cash, restricted cash and cash equivalents	$ 35,107,000	$ 33,811,000