Note 12 - Net Income Per Share (Details Textual) - shares	3 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Incremental Common Shares Attributable to Share-based Payment Arrangements, Total	68,333	307
Share-based Payment Arrangement, Option [Member]
Incremental Common Shares Attributable to Share-based Payment Arrangements, Total	85,000

Additional shares included in the calculation of diluted EPS as a result of the potentially dilutive effect of share based payment arrangements using the treasury stock method.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 260
-SubTopic 10
-Section 45
-Paragraph 28A
-URI http://asc.fasb.org/extlink&oid=117326831&loc=d3e1500-109256

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 260
-SubTopic 10
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6371337&loc=d3e3550-109257

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Balance Type:	na
Period Type:	duration