Note 4 - Receivables and Allowance for Credit Losses - Receivables (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Accounts receivable–trade	$ 26,912	$ 29,134
Less allowance for credit losses	(484)	(486)
Receivables, net	$ 26,428	$ 28,648

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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-SubTopic 210
-Section S99
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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