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Revenue Recognition - Additional Information (Details) - USD ($) | 12 Months Ended
--- | ---
Sep. 30, 2019 | Sep. 30, 2018
Disaggregation Of Revenue [Line Items] |  |
Revenue | $ 45,847,000 | $ 53,306,000
Cost of revenue recognized from deferred contract cost | 27,000 |
Deferred Revenue |  |
Disaggregation Of Revenue [Line Items] |  |
Deferred contract liabilities | 0 | 200,000
Prepaid Expenses and Other Current Assets |  |
Disaggregation Of Revenue [Line Items] |  |
Deferred contract costs | 0 | $ 27,000
Deferred Contract Liability |  |
Disaggregation Of Revenue [Line Items] |  |
Revenue | $ 200,000 |

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- Definition Amount, after allowance for credit loss, of right to consideration in exchange for good or service transferred to customer when right is conditioned on something other than passage of time, classified as current. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 606 -SubTopic 10 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=118944033&loc=SL49130531-203044 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 606 -SubTopic 10 -Section 45 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=118944033&loc=SL49130533-203044 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 606 -SubTopic 10 -Section 50 -Paragraph 8 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=118956577&loc=SL49130549-203045 + Details
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