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Revenue Recognition - Additional Information (Details) - USD ($) | 3 Months Ended | 6 Months Ended |
--- | --- | --- | ---
Mar. 31, 2019 | Mar. 31, 2019 | Sep. 30, 2018
Disaggregation Of Revenue [Line Items] |  |  |
Cost of revenue reognized from deferred contract cost | $ 0 | $ 8,000 |
Deferred Revenue |  |  |
Disaggregation Of Revenue [Line Items] |  |  |
Deferred contract liabilities | 100,000 | 100,000 | $ 200,000
Prepaid Expenses and Other Current Assets |  |  |
Disaggregation Of Revenue [Line Items] |  |  |
Deferred contract costs | $ 35,000 | $ 35,000 | $ 27,000

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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://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 606 -SubTopic 10 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=82913815&loc=SL49130531-203044 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 606 -SubTopic 10 -Section 45 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=82913815&loc=SL49130533-203044 + Details
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