Note 17 - Restricted Net Assets (Details Textual) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2019	Dec. 31, 2018
Amount of Restricted Net Assets for Consolidated and Unconsolidated Subsidiaries	$ 12	$ 12
Withholding Tax Rate Pursuant To EIT Law	10.00%
Preferential Withholding Tax Rate	5.00%
WFOE [Member]
Minimum Percentage Of Annual After-tax Profit For General Reserve	10.00%
Minimum Required Reserve As Percent Of Registered Capital	50.00%
Domestic Enterprise [Member]
Minimum Percentage Of Annual After-tax Profit For General Reserve	10.00%
Minimum Required Reserve As Percent Of Registered Capital	50.00%

Minimum percentage of annual after-tax profit required to be appropriated as general reserve.

No definition available.

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- Definition

Minimum aggregate compulsory appropriation of general reserve, measured by percentage of registered capital.

+ References

No definition available.

+ Details

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- Definition

Preferential withholding tax rate in PRC.

+ References

No definition available.

+ Details

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- Definition

Withholding tax rate pursuant to PRC Enterprise Income Tax law.

+ References

No definition available.

+ Details

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- Definition

Amount of restricted net assets of consolidated and unconsolidated subsidiaries as of the end of the most recently completed fiscal year.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(e)(3)(ii))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

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- Details

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- Details

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