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Stockholders' Equity - Additional Information (Details) - USD ($) | 12 Months Ended
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Sep. 30, 2020 | Sep. 30, 2019
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |
Intrinsic value of nonqualified stock options exercised | $ 0 | $ 100,000
Stock-based compensation expense | 2,300,000 | $ 2,300,000
Unrecognized compensation expense | 0 |
Restricted Stock Awards (RSAs) |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |
Shares issued |  | 8,000
Weighted average grant date fair value of the restricted stock issued |  | $ 14.59
Unrecognized compensation expense | $ 900,000 |
Expected period for recognition of unrecognized compensation expense | 1 year 2 months 12 days |
Restricted Stock Units (RSUs) |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |
Shares issued | 162,250 | 161,800
Weighted average grant date fair value of the restricted stock issued | $ 14.58 | $ 15.11
Unrecognized compensation expense | $ 2,400,000 |
Expected period for recognition of unrecognized compensation expense | 2 years 8 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 |
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 | 370,110 |
2014 Long Term Incentive Plan | Restricted Stock Awards (RSAs) |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |
Shares issued | 0 | 8,000
Weighted average grant date fair value of the restricted stock issued |  | $ 14.59
Grant date fair value of restricted stock issued |  | $ 100,000
Restricted stock restriction period |  | 4 years
2014 Long Term Incentive Plan | Restricted Stock Units (RSUs) |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |
Shares issued | 162,250 | 161,800
Weighted average grant date fair value of the restricted stock issued | $ 14.58 | $ 15.11
Restricted stock restriction period | 4 years | 4 years
Grant date fair value of restricted stock | $ 2,400,000 | $ 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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