Note 8 - Income Taxes (Details Textual)	6 Months Ended
Sep. 30, 2015 USD ($)
Earliest Tax Year [Member]
Open Tax Year	1999
Latest Tax Year [Member]
Open Tax Year	2014
Unrecognized Tax Benefits	$ 0
Unrecognized Tax Benefits, Interest on Income Taxes Accrued	$ 0

Tax year that remains open to examination under enacted tax laws, in CCYY format.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

-SubTopic 10

-Section 50

-Paragraph 15

-Subparagraph (e)

-URI http://asc.fasb.org/extlink&oid=6907707&loc=d3e32718-109319

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Balance Type:	na
Period Type:	duration

- Definition

Amount of unrecognized tax benefits pertaining to uncertain tax positions taken in tax returns.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

-SubTopic 10

-Section 50

-Paragraph 15A

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=6907707&loc=SL6600010-109319

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Unrecognized Tax Benefit

-URI http://asc.fasb.org/extlink&oid=6527854

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- Definition

Amount of interest expense accrued for an underpayment of income taxes.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

-SubTopic 10

-Section 50

-Paragraph 15

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=6907707&loc=d3e32718-109319

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