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Stock-Based Compensation (Tables) | 12 Months Ended
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Sep. 30, 2017
1997 Plan [Member] |
Summary of Option Activity under Stock-Based Compensation Plan | The following table summarizes option activity under the 1997 Plan:
|  | Number of Shares |  |  | Exercise Price Per Share |
Outstanding at September 30, 2014 and 2015 |  |  | 41,250 |  |  | $ | 6.213 |
Options exercised during fiscal 2016 |  |  | (30,000 | ) |  | $ | 6.213 |
Options expired during fiscal 2016 |  |  | (11,250 | ) |  | $ | 6.213 |
Options outstanding at September 30, 2016 |  |  | — |  |  |  |  |
January 19, 2016 Class B Stock Options [Member] |
Fair Value of Stock Options at Time of Grant | The following assumptions were used to determine the fair value of the stock options at time of grant:
Risk-free interest rate |  |  | 2.5 | %
Expected life of options |  |  | 10.0 years |
Dividend yield |  |  | 0.0 | %
Volatility |  |  | 29.1 | %
September 26, 2016 Class B Stock Options [Member] |
Fair Value of Stock Options at Time of Grant | The following assumptions were used to determine the fair value of the stock options at time of grant:
Risk-free interest rate |  |  | 2.25 | %
Expected life of options |  |  | 10.0 years |
Dividend yield |  |  | 0.0 | %
Volatility |  |  | 29.2 | %
2009 Plan [Member] |
Summary of Option Activity under Stock-Based Compensation Plan | The following table summarizes option activity under the 2009 Plan:
|  | Number of Shares |  |  | Average Exercise Price Per Share |
Options outstanding at September 30, 2014 |  |  | 474,750 |  |  | $ | 5.103 |
Options exercised during fiscal 2015 |  |  | (28,125 | ) |  | $ | 4.839 |
Options outstanding at September 30, 2015 |  |  | 446,625 |  |  | $ | 5.120 |
Options granted |  |  | 75,000 |  |  | $ | 8.760 |
Options exercised during fiscal 2016 |  |  | (37,875 | ) |  | $ | 5.126 |
Options outstanding at September 30, 2016 |  |  | 483,750 |  |  | $ | 5.684 |
Options exercised during fiscal 2017 |  |  | (43,750 | ) |  | $ | 5.126 |
Options outstanding at September 30, 2017 |  |  | 440,000 |  |  | $ | 5.739 |

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- Definition Tabular disclosure for share-based compensation plans. Includes, but is not limited to, outstanding awards at beginning and end of year, grants, exercises, forfeitures, and weighted-average grant date fair value. + 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)(2) -URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (e) -URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901 + Details
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- Definition Tabular disclosure of the significant assumptions used during the year to estimate the fair value of stock options, including, but not limited to: (a) expected term of share options and similar instruments, (b) expected volatility of the entity's shares, (c) expected dividends, (d) risk-free rate(s), and (e) discount for post-vesting restrictions. + 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 (f)(2) -URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901 + Details
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