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Stockholders' Equity - Additional Information (Details) - USD ($) | 12 Months Ended |
--- | --- | ---
Sep. 30, 2019 | Sep. 30, 2018 | Sep. 30, 2017
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |
Stock options outstanding | 165,600 | 190,100 | 201,800
Intrinsic value of nonqualified stock options exercised | $ 100,000 | $ 41,000 |
Stock-based compensation expense | 2,300,000 | $ 2,300,000 |
Unrecognized compensation expense | $ 8,000 |  |
Expected period for recognition of unrecognized compensation expense | 1 month 6 days |  |
Restricted Stock Awards (RSAs) |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |
Shares issued | 8,000 | 176,450 |
Weighted average grant date fair value of the restricted stock issued | $ 14.59 | $ 15.13 |
Unrecognized compensation expense | $ 2,200,000 |  |
Expected period for recognition of unrecognized compensation expense | 2 years |  |
Restricted Stock Units (RSUs) |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |
Shares issued | 161,800 |  |
Weighted average grant date fair value of the restricted stock issued | $ 15.17 |  |
Unrecognized compensation expense | $ 1,700,000 |  |
Expected period for recognition of unrecognized compensation expense | 3 years 2 months 12 days |  |
1997 Plan |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |
Common stock reserved for issuance | 2,250,000 |  |
Expiration date | 2017-11 |  |
Common stock available for issuance | 0 |  |
Stock options outstanding | 45,000 |  |
2014 Long Term Incentive Plan |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |
Common stock reserved for issuance | 1,500,000 |  |
Percent of outstanding common stock granted to employees | 10.00% |  |
Exercise price of stock option granted to employees | 110.00% |  |
Common stock available for issuance | 477,015 |  |
2014 Long Term Incentive Plan | Restricted Stock Awards (RSAs) |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |
Shares issued | 8,000 | 176,450 |
Weighted average grant date fair value of the restricted stock issued | $ 14.59 | $ 15.13 |
Grant date fair value of restricted stock issued | $ 100,000 | $ 2,700,000 |
Restricted stock restriction period | 4 years | 4 years |
2014 Long Term Incentive Plan | Restricted Stock Units (RSUs) |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |
Shares issued | 161,800 |  |
Weighted average grant date fair value of the restricted stock issued | $ 15.11 |  |
Restricted stock restriction period | 4 years |  |
Grant date fair value of restricted stock | $ 2,400,000 |  |
2014 Long Term Incentive Plan | Maximum |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |
Options have a term | 10 years |  |
Outstanding shares of common stock granted to employees expiry term | 5 years |  |

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