Note 11 - Acquisition of Businesses - Aggregate Consideration (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Feb. 01, 2021	Dec. 31, 2020
Goodwill	$ 36,197		$ 36,116
CID Resources [Member]
Accounts receivable		$ 251
Prepaid expenses and other current assets		196
Property, plant and equipment		60
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Intangible Assets, Other than Goodwill, Total		5,939
Goodwill		125
Total assets		6,571
Accounts payable		199
Other current liabilities		372
Total liabilities		$ 571

Amount of assets acquired at the acquisition date.

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Amount due from customers or clients for goods or services, including trade receivables, that have been delivered or sold in the normal course of business, and amounts due from others, including related parties expected to be converted to cash, sold or exchanged within one year or the normal operating cycle, if longer, acquired at the acquisition date.

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The amount of property, plant, and equipment recognized as of the acquisition date.

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Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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