Note 6 - Goodwill and Intangible Assets (Details Textual) - USD ($)	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Goodwill, Impairment Loss	$ 0	$ 714,000
Amortization of Intangible Assets, Total	320,000	318,000	$ 374,000
Finite-Lived Intangible Asset, Expected Amortization, Year One	180,000
Finite-Lived Intangible Asset, Expected Amortization, Year Two	140,000
Finite-Lived Intangible Asset, Expected Amortization, Year Three	140,000
Finite-Lived Intangible Asset, Expected Amortization, Year Four	139,000
Canadian Subsidiary [Member]
Goodwill, Impairment Loss	$ 714,000	$ 714,000

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 loss from the write-down 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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