Note 8 - Leases (Details Textual)	1 Months Ended	3 Months Ended		6 Months Ended
	Jun. 30, 2021 USD ($)	Jun. 30, 2022 USD ($)	Jun. 30, 2021 USD ($)	Jun. 30, 2022 USD ($)	Jun. 30, 2021 USD ($)	Mar. 31, 2021	Oct. 01, 2020	Feb. 01, 2017 USD ($) ft²
Operating Lease, Expense		$ 69,000	$ 69,000	$ 138,000	$ 149,000
Operating Lease, Weighted Average Remaining Lease Term (Month)		21 months		21 months
Operating Lease, Weighted Average Discount Rate, Percent		12.50%		12.50%
Sublease Agreement for Relocation of Headquarters [Member]
Area of Real Estate Property (Square Foot) | ft²								12,400
Lessee, Operating Lease, Term of Contract (Month)								36 months
Security Deposit								$ 22,000
Operating Leases, Allowance for Certain Improvements								$ 88,000
Lessee, Operating Lease, Renewal Term (Month)						34 months
Lessee, Operating Lease, Rent Abatement	$ 19,000
Noncancelable Operating Lease Agreement for Office Equipment [Member]
Lessee, Operating Lease, Term of Contract (Month)							36 months
Leases of Viveve Systems [Member]
Property, Plant, and Equipment, Lessor Asset under Operating Lease, after Accumulated Depreciation, Total		$ 397,000		$ 397,000
Depreciation, Lessor Asset under Operating Lease		$ 55,000	$ 60,000	$ 113,000	$ 170,000