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Employee Benefit Plans - Additional Information (Detail) - USD ($) | 12 Months Ended
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Sep. 30, 2015 | Sep. 30, 2014 | Sep. 30, 2013
Defined Benefit Plan Disclosure [Line Items] |  |  |
Employee benefits costs | $ 407,603 | $ 264,193 | $ 191,947
Discretionary Contributions |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Discretionary match percentage | 100.00% |  |
Employee Contributions up to 3% |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Percentage of compensation | 3.00% |  |
Employee Contributions Next 2% |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Discretionary match percentage | 50.00% |  |
Percentage of compensation | 2.00% |  |

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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
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- Definition The amount of the cost recognized during the period for defined contribution plans. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 70 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=49170846&loc=d3e28014-114942 + Details
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- Definition Percentage employer matches of the employee's percentage contribution matched. + References No definition available. + Details
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