Note 7 - Leases (Details Textual)	1 Months Ended	3 Months Ended		9 Months Ended
	Sep. 30, 2018 USD ($)	Sep. 30, 2019 USD ($)	Sep. 30, 2018 USD ($)	Sep. 30, 2019 USD ($)	Sep. 30, 2018 USD ($)	Feb. 01, 2017 USD ($) ft²
Operating Leases, Rent Expense, Total			$ 65,000		$ 293,000
Operating Lease, Cost		$ 75,000		$ 225,000
Operating Lease, Weighted Average Discount Rate, Percent		12.50%		12.50%
Sublease Agreement for Relocation of Headquarters [Member]
Area of Real Estate Property | ft²						12,400
Operating Leases, Monthly Rent Per Rentable Square Foot During First Year						20.5
Operating Leases, Monthly Rent Per Rentable Square Foot During Second Year						21.12
Operating Leases, Monthly Rent Per Rentable Square Foot During Third Year						21.75
Security Deposit						$ 22,000
Operating Leases, Allowance for Certain Improvements						$ 88,000
Noncancelable Operating Lease Agreement for Office Equipment [Member]
Lessee, Operating Lease, Term of Contract	3 years		3 years		3 years
Operating Leases, Monthly Payment	$ 3,000
Leases of Viveve Systems [Member]
Operating Lease, Property Plant and Equipment, Amount		$ 456,000		$ 456,000
Lessor, Operating Lease, Depreciation on Leased Assets		$ 46,000		$ 46,000