Note 9 - Cash, Cash Equivalents, Investments and Restricted Cash - Investment Maturity Classification (Details) $ in Thousands	Sep. 30, 2021 USD ($)
Due in less than 1 year, Amortized cost	$ 113,987
Due in less than 1 year, fair value	114,265
Due in 1 - 5 years, Amortized cost	401,166
Due in 1 - 5 years	401,682
Due in greater than 5 years, Amortized cost	2,620
Due in greater than 5 years	2,501
Total, Amortized cost	517,773
Total	$ 518,448

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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