Note 2 - Recent Accounting Pronouncements (Details Textual) - Accounting Standards Update 2016-09 [Member]	3 Months Ended
Dec. 31, 2016 USD ($)
Excess Tax Benefit from Share-based Compensation, Operating Activities	$ 100,000
Excess Tax Benefit from Share-based Compensation, Financing Activities	$ (100,000)

Amount of cash outflow for realized tax benefit related to deductible compensation cost reported on the entity's tax return for equity instruments in excess of the compensation cost for those instruments recognized for financial reporting purposes.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 20
-Section 55
-Paragraph 24
-URI http://asc.fasb.org/extlink&oid=96864182&loc=d3e11374-113907

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration