Note 11 - Subsequent Event	3 Months Ended
Mar. 31, 2021
Notes to Financial Statements
Subsequent Events [Text Block]	11. Subsequent Event In April 2021, Velano Vascular was acquired by another entity. The Company received $3.4 million in initial cash proceeds and may receive additional amounts over the next 12 months from the resolution of escrow contingencies. In May 2021, the Company's Board of Directors authorized a new $6 million share repurchase program using existing funds in accordance with the requirements Rule 10b5-1 and Rule 10b-18 under the Securities Exchange Act of 1934, as amended.

The entire disclosure for significant events or transactions that occurred after the balance sheet date through the date the financial statements were issued or the date the financial statements were available to be issued. Examples include: the sale of a capital stock issue, purchase of a business, settlement of litigation, catastrophic loss, significant foreign exchange rate changes, loans to insiders or affiliates, and transactions not in the ordinary course of business.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 855
-URI http://asc.fasb.org/topic&trid=2122774

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 855
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=6842918&loc=SL6314017-165662

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