Note 9 - Cash, Cash Equivalents, Investments and Restricted Cash - Investment Maturity Classification (Details) $ in Thousands	Mar. 31, 2022 USD ($)
Due in less than 1 year, Amortized cost	$ 250,562
Due in less than 1 year, fair value	249,994
Due in 1 - 5 years, Amortized cost	269,548
Due in 1 - 5 years	262,914
Due in greater than 5 years, Amortized cost	2,495
Due in greater than 5 years	2,376
Total, Amortized cost	522,605
Total	$ 515,284

Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), with single maturity date and allocated without single maturity date, maturing in sixth through tenth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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