Note 1 - Basis of Presentation (Details Textual) - USD ($)		3 Months Ended
Jul. 26, 2021	Dec. 31, 2020
Asset Impairment Charges, Total		$ 3,600,000
The Premises at 555 N Research Place, Central Islip, NY [Member] \| Subsequent Event [Member]
Proceeds from Sale of Buildings	$ 24,360,000
Proceeds from Sale of Buildings, Net	14,000,000
The Premises at 555 N Research Place, Central Islip, NY [Member] \| Subsequent Event [Member] \| HSBC Bank Second Mortgage Loan [Member]
Repayments of Debt	$ 9,352,719

The cash inflow from sale of buildings, net of cash outflows.

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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
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-Section 45
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=123351718&loc=d3e2420-110228

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The cash inflow from sale of buildings.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 12
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=123570139&loc=d3e3179-108585

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- Definition

The cash outflow during the period from the repayment of aggregate short-term and long-term debt. Excludes payment of capital lease obligations.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 15
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=123570139&loc=d3e3291-108585

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