Note 8 - Variable Interest Entity - Carrying amounts (Details) - Variable Interest Entity, Primary Beneficiary [Member]	Mar. 31, 2018 USD ($)
Current assets	$ 100,497
Total assets	100,497
Current liabilities	19,331
Total liabilities	$ 19,331

Amount of consolidated variable interest entity's (VIE) assets that can only be used to settle obligations of the VIE, classified as current.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 810
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (bb)
-URI http://asc.fasb.org/extlink&oid=108788376&loc=d3e5710-111685

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 810
-SubTopic 10
-Section 45
-Paragraph 25
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=6839525&loc=SL6758485-165988

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Amount of consolidated variable interest entity's (VIE) assets that can only be used to settle obligations of VIE.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 810
-SubTopic 10
-Section 45
-Paragraph 25
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=6839525&loc=SL6758485-165988

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 810
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (bb)
-URI http://asc.fasb.org/extlink&oid=108788376&loc=d3e5710-111685

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Namespace Prefix:	us-gaap_
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Balance Type:	debit
Period Type:	instant

- Definition

Amount of consolidated variable interest entity's (VIE) liabilities that have recourse to general credit of primary beneficiary, classified as current.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 810
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=108788376&loc=d3e5710-111685

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 810
-SubTopic 10
-Section 45
-Paragraph 25
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=6839525&loc=SL6758485-165988

+ Details

Name:	us-gaap_VariableInterestEntityConsolidatedLiabilitiesCurrentRecourse
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of consolidated variable interest entity's (VIE) liabilities that have recourse to general credit of primary beneficiary.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 810
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=108788376&loc=d3e5710-111685

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 810
-SubTopic 10
-Section 45
-Paragraph 25
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=6839525&loc=SL6758485-165988

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Details

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Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: