Note 4 - Inventories (Details Textual) - USD ($)	Mar. 31, 2021	Dec. 31, 2020
Inventory Valuation Reserves, Ending Balance	$ 450,000	$ 453,000
Slow Moving Medical Finished Goods [Member]
Inventory Valuation Reserves, Ending Balance	$ 450,000	450,000
Slow Moving Dental Finished Goods [Member]
Inventory Valuation Reserves, Ending Balance		$ 3,000

Amount of valuation reserve for inventory.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 330
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SAB TOPIC 5.BB)
-URI http://asc.fasb.org/extlink&oid=27011343&loc=d3e100047-122729

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 4
-Subparagraph (SX 210.12-09)
-URI http://asc.fasb.org/extlink&oid=120395691&loc=d3e24092-122690

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.6(a))
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

Name:	us-gaap_InventoryValuationReserves
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant