Note 6 - Goodwill and Intangible Assets (Details Textual) - USD ($)	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019
Goodwill, Purchase Accounting Adjustments	$ (131,000)
Increase (Decrease) in Accounts Payable, Total	(171,000)	$ 768,000
Amortization of Intangible Assets, Total	3,033,000	$ 1,079,000
CBS Acquisition [Member] \| Immaterial Error [Member]
Goodwill, Purchase Accounting Adjustments	(131,000)
Increase (Decrease) in Accounts Payable, Total	$ (131,000)

The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

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Amount of increase (decrease) from adjustments after acquisition date under purchase accounting of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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