Note 3 - Cash, Cash Equivalents, Investments and Restricted Cash - Restricted Cash (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Cash and cash equivalents	$ 288,607	$ 189,265
Restricted cash included in other long-term assets	122	124
Total cash, cash equivalents and restricted cash reported on the Consolidated Statements of Cash Flows	$ 288,729	$ 189,389	$ 335,071	$ 173,076