Note 9 - Cash, Cash Equivalents, Investments and Restricted Cash - Investment Maturity Classification (Details) $ in Thousands	Jun. 30, 2021 USD ($)
Due in less than 1 year, Amortized cost	$ 100,111
Due in less than 1 year, fair value	100,422
Due in 1 - 5 years, Amortized cost	348,856
Due in 1 - 5 years	349,656
Due in greater than 5 years, Amortized cost	2,720
Due in greater than 5 years	2,582
Total, Amortized cost	451,687
Total	$ 452,660

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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