Note 1 - Nature of Operations, Basis of Presentation and Consolidation (Details Textual) ¥ in Millions, $ in Millions	6 Months Ended
Jun. 30, 2020 shares	Jun. 30, 2019 shares	Dec. 31, 2019 USD ($)	Dec. 31, 2019 CNY (¥)
Restricted Stock [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount (in shares)	892,083	55,430
CHINA
Restricted Cash and Cash Equivalents, Total			$ 2.9	¥ 20

Amount of cash and cash equivalents restricted as to withdrawal or usage. Cash includes, but is not limited to, currency on hand, demand deposits with banks or financial institutions, and other accounts with general characteristics of demand deposits. Cash equivalents include, but are not limited to, short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant