Note 2 - Summary of Significant Accounting Policies (Details Textual)	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2022 USD ($) $ / shares shares	Jun. 30, 2021 USD ($) shares	Jun. 30, 2022 USD ($) $ / shares shares	Jun. 30, 2021 USD ($) shares	Dec. 31, 2021 USD ($) shares	Mar. 31, 2022 USD ($)	Mar. 14, 2022 shares	Mar. 31, 2021 USD ($)	Jan. 31, 2021 shares
Number of Financial Institutions	1		1
Accounts Receivable, Allowance for Credit Loss, Writeoff	$ 30,000	$ 64,000	$ 58,000	$ 74,000
Revenue from Contract with Customer, Excluding Assessed Tax	1,795,000	1,654,000	3,436,000	3,104,000
Contract with Customer, Asset, after Allowance for Credit Loss, Total					$ 0	$ 0
Contract with Customer, Liability, Total	6,000		6,000		7,000
Capitalized Contract Cost, Net, Total	48,000		48,000		$ 84,000
Capitalized Contract Cost, Amortization	20,000	20,000	37,000	34,000
Capitalized Contract Cost, Impairment Loss			0
Equity Method Investment, Other than Temporary Impairment	$ 455,000	$ (0)	$ 455,000	$ 0
Series B Preferred Stock [Member]
Preferred Stock, Shares Outstanding, Ending Balance (in shares) | shares	43,069	38,090	43,069	38,090	40,504
Convertible Preferred Stock, Shares Issued upon Conversion (in shares) | shares	2,814,967	2,489,542	2,814,967	2,489,542	2,647,320
Series B Preferred Stock [Member] | Conversion From Series B Preferred Stock to Common Stock [Member]
Preferred Stock, Convertible, Conversion Ratio	65.36		65.36
Preferred Stock, Liquidation Preference Per Share (in dollars per share) | $ / shares	$ 1,000		$ 1,000
Preferred Stock, Convertible, Conversion Price (in dollars per share) | $ / shares	$ 15.30		$ 15.30
Series C Preferred Stock [Member]
Preferred Stock, Shares Outstanding, Ending Balance (in shares) | shares	0		0		0		0		0
Convertible Preferred Stock, Shares Issued upon Conversion (in shares) | shares	1		1
Rental [Member]
Revenue from Contract with Customer, Excluding Assessed Tax	$ 273,000	$ 323,000	$ 534,000	$ 689,000
Contract with Customer, Liability, Current	464,000		464,000					$ 452,000
Contract with Customer, Liability, Revenue Recognized	$ 118,000	$ 66,000	$ 315,000	$ 296,000
Minimum [Member]
Warranty Period (Year)			1 year
Minimum [Member] | Viveve Systems [Member]
Lessor, Operating Lease, Term of Contract (Month)	6 months		6 months
Maximum [Member]
Warranty Period (Year)			3 years
Maximum [Member] | Viveve Systems [Member]
Lessor, Operating Lease, Term of Contract (Month)	12 months		12 months
Customer Concentration Risk [Member] | Revenue Benchmark [Member]
Concentration Risk, Number of Customers	1	1	1	1
Customer Concentration Risk [Member] | Revenue Benchmark [Member] | One Customer [Member]
Concentration Risk, Percentage	29.00%	34.00%	35.00%	26.00%
Customer Concentration Risk [Member] | Accounts Receivable [Member]
Concentration Risk, Number of Customers			1		1
Customer Concentration Risk [Member] | Accounts Receivable [Member] | One Customer [Member]
Concentration Risk, Percentage			39.00%		10.00%