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Loss Per Common Share - Additional Information (Details) | 3 Months Ended | 9 Months Ended
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Jun. 30, 2019 shares | Jun. 30, 2018 shares | Jun. 30, 2019 shares | Jun. 30, 2018 shares
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items] |  |  |  |
Split of common stock ratio |  |  | 2 |
Stock Options |  |  |  |
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items] |  |  |  |
Number of stock excluded from calcuation of weighted average shares outstandiing | 163,800 | 194,600 | 163,800 | 194,600
Non-Vested RSUs |  |  |  |
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items] |  |  |  |
Number of stock excluded from calcuation of weighted average shares outstandiing | 161,300 | 0 | 161,300 | 0

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- Definition Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 260 -SubTopic 10 -Section 50 -Paragraph 1 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=6371337&loc=d3e3550-109257 + Details
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