Note 3 - Cash, Cash Equivalents, Investments and Restricted Cash - Investment Maturity Classification (Details) $ in Thousands	Dec. 31, 2020 USD ($)
Due in less than 1 year, Amortized cost	$ 97,773
Due in less than 1 year, fair value	98,036
Due in 1 - 5 years, Amortized cost	160,316
Due in 1 - 5 years	162,133
Due in greater than 5 years, Amortized cost	3,020
Due in greater than 5 years	2,861
Total, Amortized cost	261,109
Total	$ 263,030

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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