Note 3 - Cash, Cash Equivalents, Investments and Restricted Cash - Investment Maturity Classification (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Due in less than 1 year	$ 147,532	$ 125,845
Due in 1 - 5 years	134,905	78,732
Due in greater than 5 years	3,138	3,241
Total	$ 285,575	$ 207,818

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 fiscal year through tenth fiscal year following latest fiscal year. Excludes interim and annual periods when interim period is reported on rolling approach, from latest statement of financial position date.

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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 second through fifth fiscal year following latest fiscal year. Excludes interim and annual periods when interim period is reported on rolling approach, from latest statement of financial position date.

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