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Stockholders' Equity - Additional Information (Details) - USD ($) $ / shares in Units, $ in Millions | 12 Months Ended
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Sep. 30, 2016 | Sep. 30, 2015 | Sep. 30, 2014
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |
Weighted average grant date fair value of the restricted stock | $ 14.84 | $ 19.13 | $ 95.18
Expected period for recognition of unrecognized compensation expense | 1 year 6 months |  |
Nonqualified stock options exercised | 0 | 0 | 16,350
Intrinsic value of nonqualified stock options exercised |  |  | $ 0.7
Stock-based compensation expense | $ 5.2 | $ 5.6 | $ 5.4
Unrecognized compensation expense | $ 0.2 |  |
Restricted Stock |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |
Expected period for recognition of unrecognized compensation expense | 2 years 7 months 6 days |  |
Unrecognized compensation expense | $ 6.9 |  |
Maximum |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |
Expected period for recognition of unrecognized compensation expense | 4 years |  |
1997 Plan |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |
Common stock reserved for issuance | 2,250,000 |  |
Expiration date | Nov. 14, 2017 |  |
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 | 1,134,600 |  |
Shares issued | 69,300 |  |
Stock options, weighted average grant date fair value | $ 5.96 |  |
2014 Long Term Incentive Plan | Restricted Stock |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |
Shares issued | 182,400 |  |
Weighted average grant date fair value of the restricted stock | $ 14.84 |  |
Grant date fair value of restricted stock | $ 2.7 |  |
Restricted stock restriction period | 4 years |  |
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 |  |
Expected period for recognition of unrecognized compensation expense | 36 months |  |
2014 Long Term Incentive Plan | Minimum |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |
Expected period for recognition of unrecognized compensation expense | 18 months |  |

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