Note 5 - Fair Value Measurement - Assets and Liabilities Measured at Fair Value (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Corporate bonds	$ 112,080	$ 90,298
Foreign exchange contract	13	63
Investments in marketable equity securities	408	2,919
Foreign exchange contracts	119
Fair Value, Inputs, Level 1 [Member]
Foreign exchange contract	0	0
Investments in marketable equity securities	408	2,919
Foreign exchange contracts	0
Fair Value, Inputs, Level 2 [Member]
Foreign exchange contract	13	63
Investments in marketable equity securities	0	0
Foreign exchange contracts	119
Fair Value, Inputs, Level 3 [Member]
Foreign exchange contract	0	0
Investments in marketable equity securities	0	0
Foreign exchange contracts	0
Corporate Bonds [Member]
Corporate bonds	112,080	90,298
Corporate Bonds [Member] | Fair Value, Inputs, Level 1 [Member]
Corporate bonds	0	0
Corporate Bonds [Member] | Fair Value, Inputs, Level 2 [Member]
Corporate bonds	112,080	90,298
Corporate Bonds [Member] | Fair Value, Inputs, Level 3 [Member]
Corporate bonds	$ 0	$ 0