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Summary of Stock Options Outstanding and Exercisable (Details) - USD ($) | 12 Months Ended |  |  |
--- | --- | --- | --- | ---
Sep. 30, 2016 | Sep. 30, 2015 | Sep. 30, 2014 | Sep. 30, 2013
Share Based Compensation Shares Authorized Under Stock Option Plans Exercise Price Range [Line Items] |  |  |  |
Options Outstanding Shares | 159,000 | 89,700 | 89,700 | 106,050
Options Outstanding, Weighted Average Remaining Term | 5 years 8 months 12 days |  |  |
Options Outstanding Weighted Average Exercise Price | $ 16.23 | $ 17.27 | $ 17.27 | $ 18.61
Options Outstanding Intrinsic Value | $ 728,213 |  |  |
Options Exercisable Shares | 89,700 |  |  |
Option Exercisable Weighted Average Remaining Term | 3 years |  |  |
Options Exercisable Weighted Average Exercise Price | $ 17.27 |  |  |
Options Exercisable Intrinsic Value | $ 408,740 |  |  |
Range One |  |  |  |
Share Based Compensation Shares Authorized Under Stock Option Plans Exercise Price Range [Line Items] |  |  |  |
Range of Exercise Prices Minimum | $ 8.78 |  |  |
Range of Exercise Prices Maximum | $ 8.78 |  |  |
Options Outstanding Shares | 38,200 |  |  |
Options Outstanding, Weighted Average Remaining Term | 2 years 2 months 12 days |  |  |
Options Outstanding Weighted Average Exercise Price | $ 8.78 |  |  |
Options Outstanding Intrinsic Value | $ 408,740 |  |  |
Options Exercisable Shares | 38,200 |  |  |
Option Exercisable Weighted Average Remaining Term | 2 years 2 months 12 days |  |  |
Options Exercisable Weighted Average Exercise Price | $ 8.78 |  |  |
Options Exercisable Intrinsic Value | $ 408,740 |  |  |
Range Two |  |  |  |
Share Based Compensation Shares Authorized Under Stock Option Plans Exercise Price Range [Line Items] |  |  |  |
Range of Exercise Prices Minimum | $ 14.87 |  |  |
Range of Exercise Prices Maximum | $ 14.87 |  |  |
Options Outstanding Shares | 69,300 |  |  |
Options Outstanding, Weighted Average Remaining Term | 9 years 1 month 6 days |  |  |
Options Outstanding Weighted Average Exercise Price | $ 14.87 |  |  |
Options Outstanding Intrinsic Value | $ 319,473 |  |  |
Range Three |  |  |  |
Share Based Compensation Shares Authorized Under Stock Option Plans Exercise Price Range [Line Items] |  |  |  |
Range of Exercise Prices Minimum | $ 21.95 |  |  |
Range of Exercise Prices Maximum | $ 26.48 |  |  |
Options Outstanding Shares | 51,500 |  |  |
Options Outstanding, Weighted Average Remaining Term | 3 years 7 months 6 days |  |  |
Options Outstanding Weighted Average Exercise Price | $ 23.57 |  |  |
Options Exercisable Shares | 51,500 |  |  |
Option Exercisable Weighted Average Remaining Term | 3 years 7 months 6 days |  |  |
Options Exercisable Weighted Average Exercise Price | $ 23.57 |  |  |

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- Definition The floor of a customized range of exercise prices for purposes of disclosing shares potentially issuable under outstanding stock option awards on all stock option plans and other required information pertaining to awards in the customized range. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (g) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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- Definition The number of shares reserved for issuance pertaining to the outstanding exercisable stock options as of the balance sheet date in the customized range of exercise prices for which the market and performance vesting condition has been satisfied. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(iii) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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- Definition The ceiling of a customized range of exercise prices for purposes of disclosing shares potentially issuable under outstanding stock option awards on all stock option plans and other required information pertaining to awards in the customized range. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (g) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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