Note 16 - Related Party Transactions (Details Textual) - USD ($)				3 Months Ended		9 Months Ended
	May 15, 2020	May 13, 2020	Aug. 08, 2019	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019	Dec. 31, 2019
Accounts Receivable, Related Parties				$ 0		$ 0		$ 0
Accounts Payable, Related Parties				0		0		$ 0
Related Party Transaction, Expenses from Transactions with Related Party				160,000	$ 162,000	251,000	$ 376,000
Stock Issued During Period, Shares, New Issues (in shares)			4,198,566
Proceeds from Issuance of Common Stock			$ 4,200,000			5,220,000	$ 6,700,000
Pioneer Hong Kong [Member] | Promissory Note [Member]
Repayments of Long-term Debt, Total	$ 1,000,000
TLF Bio Innovation [Member]
Related Party Transaction, Expenses from Transactions with Related Party				113,000		188,000
Stock Issued During Period, Shares, New Issues (in shares)		1,000
Proceeds from Issuance of Common Stock		$ 1,000
TLF Bio Innovation [Member] | Consulting Service Expense [Member]
Related Party Transaction, Expenses from Transactions with Related Party				$ 109,000		$ 109,000