Note 7 - Accounts Receivable - Summary of Accounts Receivable (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Mar. 31, 2020
Accounts receivable (billed)	$ 10,865	$ 11,276
Accounts receivable (unbilled)	5,968	5,711
Less: Allowance for doubtful accounts	(23)
Accounts receivable, net	$ 16,810	$ 16,987

Amount, after allowance for credit loss, of right to consideration from customer for product sold and service rendered in normal course of business, classified as current.

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Amount of allowance for credit loss on accounts receivable.

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