Note 4 - Receivables and Allowance for Credit Losses - Receivables (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Mar. 31, 2020
Accounts receivable–trade	$ 26,912	$ 30,542
Less allowance for credit losses	(484)	(524)
Receivables, net	$ 26,428	$ 30,018

The total amount due to the entity within one year of the balance sheet date (or one operating cycle, if longer) from outside sources, including trade accounts receivable, notes and loans receivable, as well as any other types of receivables, net of allowances established for the purpose of reducing such receivables to an amount that approximates their net realizable value.

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-Publisher FASB
-Name Accounting Standards Codification
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 946
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-Name Accounting Standards Codification
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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant