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Stockholders' Equity - Additional Information (Details) - USD ($) | 12 Months Ended
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Sep. 30, 2017 | Sep. 30, 2016 | Sep. 30, 2015
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |
Weighted average grant date fair value of the restricted stock | $ 21.12 | $ 14.84 | $ 19.13
Expected period for recognition of unrecognized compensation expense | 1 year 3 months 19 days |  |
Nonqualified stock options exercised | 4,000 | 0 | 0
Intrinsic value of nonqualified stock options exercised | $ 45,000 |  |
Stock-based compensation expense | 5,700,000 | $ 5,200,000 | $ 4,500,000
Unrecognized compensation expense | $ 400,000 |  |
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 7 days |  |
Unrecognized compensation expense | $ 3,700,000 |  |
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 | 923,175 |  |
Shares issued | 51,300 |  |
Stock options, weighted average grant date fair value | $ 9.35 |  |
2014 Long Term Incentive Plan | Restricted Stock |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |
Shares issued | 109,500 |  |
Weighted average grant date fair value of the restricted stock | $ 21.12 |  |
Grant date fair value of restricted stock | $ 2,300,000 |  |
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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- Definition Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SAB Topic 14.F) -URI http://asc.fasb.org/extlink&oid=27013229&loc=d3e301413-122809 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5047-113901 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (h)(1)(i) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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- Definition The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan). + 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)(iii)(1) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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- Definition The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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- Definition Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + 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 (a)(2) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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