Note 9 - Cash, Cash Equivalents, Investments and Restricted Cash - Investment Maturity Classification (Details) $ in Thousands	Sep. 30, 2020 USD ($)
Due in less than 1 year, Amortized cost	$ 156,119
Due in less than 1 year, fair value	156,891
Due in 1 - 5 years, Amortized cost	212,464
Due in 1 - 5 years	215,185
Due in greater than 5 years, Amortized cost	3,070
Due in greater than 5 years	2,916
Total, Amortized cost	371,653
Total	$ 374,992

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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