Note 1 - Summary of Significant Accounting Policies (Details Textual) - USD ($)	3 Months Ended	12 Months Ended
Mar. 31, 2022	Mar. 31, 2021	Dec. 31, 2021
Incremental Costs of Obtaining a Contract, Deferred During Period	$ 234,000	$ 941,000
Capitalized Contract Cost, Net, Noncurrent	3,498,000		$ 3,772,000
Capitalized Contract Cost, Impairment Loss	1,000	7,000
Operating Lease, Impairment Loss		$ 324,000	324,000
Asset Impairment Charges, Total	$ 0		$ 0
Minimum [Member]
Capitalized Contract Cost, Amortization Period (Year)	3 years
Maximum [Member]
Capitalized Contract Cost, Amortization Period (Year)	5 years

Represents the amount of incremental costs of obtaining a contract deferred during the period.

No definition available.

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- Definition

Amount of write-down of assets recognized in the income statement. Includes, but is not limited to, losses from tangible assets, intangible assets and goodwill.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
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-Topic 360
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-Section 45
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- Definition

Amortization period of cost capitalized in obtaining or fulfilling contract with customer, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 340
-SubTopic 40
-Section 50
-Paragraph 2
-Subparagraph (b)
-URI https://asc.fasb.org/extlink&oid=126905575&loc=SL49131251-203054

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- Definition

Amount of impairment loss for asset recognized from cost incurred to obtain or fulfill contract with customer.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 340
-SubTopic 40
-Section 50
-Paragraph 3
-Subparagraph (b)
-URI https://asc.fasb.org/extlink&oid=126905575&loc=SL49131252-203054

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- Definition

Amount, after accumulated amortization and accumulated impairment loss, of asset recognized from cost incurred to obtain or fulfill contract with customer; classified as noncurrent.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 340
-SubTopic 40
-Section 50
-Paragraph 3
-Subparagraph (a)
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- Definition

Amount of loss from impairment of right-of-use asset from operating lease.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 25
-Paragraph 6
-Subparagraph (c)
-URI https://asc.fasb.org/extlink&oid=123399704&loc=SL77918431-209957

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