Note 10 - Fair Value Measurements - Financial Assets and Liabilities, Fair Value (Details) - USD ($) $ in Thousands	Mar. 31, 2025	Dec. 31, 2024
Total Fair Value	$ 649,712	$ 183,145
Assets, fair value	715,489	248,482
Fair Value, Inputs, Level 1 [Member]
Assets, fair value	326,080	77,204
Fair Value, Inputs, Level 2 [Member]
Assets, fair value	389,310	171,130
Fair Value, Inputs, Level 3 [Member]
Assets, fair value	99	148
Money Market Funds [Member]
Total Fair Value	260,303	11,867
Money Market Funds [Member] | Fair Value, Inputs, Level 1 [Member]
Total Fair Value	260,303	11,867
Money Market Funds [Member] | Fair Value, Inputs, Level 2 [Member]
Total Fair Value	0	0
Money Market Funds [Member] | Fair Value, Inputs, Level 3 [Member]
Total Fair Value	0	0
Certificates of Deposit [Member]
Total Fair Value	179,117	164,418
Certificates of Deposit [Member] | Fair Value, Inputs, Level 1 [Member]
Total Fair Value	0	0
Certificates of Deposit [Member] | Fair Value, Inputs, Level 2 [Member]
Total Fair Value	179,117	164,418
Certificates of Deposit [Member] | Fair Value, Inputs, Level 3 [Member]
Total Fair Value	0	0
Corporate Debt Securities [Member]
Total Fair Value	3,247	6,712
Corporate Debt Securities [Member] | Fair Value, Inputs, Level 1 [Member]
Total Fair Value	0	0
Corporate Debt Securities [Member] | Fair Value, Inputs, Level 2 [Member]
Total Fair Value	3,247	6,712
Corporate Debt Securities [Member] | Fair Value, Inputs, Level 3 [Member]
Total Fair Value	0	0
US Government Agencies Short-Term Debt Securities [Member]
Total Fair Value	206,946
US Government Agencies Short-Term Debt Securities [Member] | Fair Value, Inputs, Level 1 [Member]
Total Fair Value	0
US Government Agencies Short-Term Debt Securities [Member] | Fair Value, Inputs, Level 2 [Member]
Total Fair Value	206,946
US Government Agencies Short-Term Debt Securities [Member] | Fair Value, Inputs, Level 3 [Member]
Total Fair Value	0
Auction Rate Securities [Member]
Total Fair Value	99	148
Auction Rate Securities [Member] | Fair Value, Inputs, Level 1 [Member]
Total Fair Value	0	0
Auction Rate Securities [Member] | Fair Value, Inputs, Level 2 [Member]
Total Fair Value	0	0
Auction Rate Securities [Member] | Fair Value, Inputs, Level 3 [Member]
Total Fair Value	99	148
Mutual Fund [Member]
Total Fair Value	65,777	65,337
Mutual Fund [Member] | Fair Value, Inputs, Level 1 [Member]
Total Fair Value	65,777	65,337
Mutual Fund [Member] | Fair Value, Inputs, Level 2 [Member]
Total Fair Value	0	0
Mutual Fund [Member] | Fair Value, Inputs, Level 3 [Member]
Total Fair Value	$ 0	$ 0