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Commitments and Contingencies - Additional Information (Details) - USD ($) |  | 12 Months Ended
--- | --- | ---
Jul. 27, 2018 | Sep. 30, 2018 | Sep. 30, 2017 | Sep. 30, 2016
Commitments And Contingencies [Line Items] |  |  |  |
Contingent earn-out liability |  | $ 7,713,000 |  |
Rent expense under Operating Leases |  | $ 100,000 | $ 100,000 | $ 200,000
Maximum |  |  |  |
Commitments And Contingencies [Line Items] |  |  |  |
Operating lease term |  | 1 year |  |
Quantum |  |  |  |
Commitments And Contingencies [Line Items] |  |  |  |
Contingent earn-out liability | $ 7,700,000 |  |  |
Contingent payments earn-out period | 4 years |  |  |
Contingent payments maximum earn-out amount | $ 23,500,000 |  |  |

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- Definition Business combination contingent consideration earn-out period. + References No definition available. + Details
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- Definition Commitments and contingencies. + References No definition available. + Details
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- Definition For contingent consideration arrangements recognized in connection with a business combination, this element represents an estimate of the high-end of the potential range (undiscounted) of the consideration which may be paid. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 30 -Section 50 -Paragraph 1 -Subparagraph (c)(3) -URI http://asc.fasb.org/extlink&oid=35744584&loc=d3e6927-128479 + Details
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- Definition Amount of liability recognized arising from contingent consideration in a business combination, expected to be settled beyond one year or the normal operating cycle, if longer. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 30 -Section 25 -Paragraph 6 -URI http://asc.fasb.org/extlink&oid=6911189&loc=d3e6408-128476 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 30 -Section 35 -Paragraph 1 -Subparagraph b -URI http://asc.fasb.org/extlink&oid=6911338&loc=d3e6819-128478 + Details
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- Definition Term of lessee's operating lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 20 -Section 50 -Paragraph 3 -Subparagraph (a)(3) -URI http://asc.fasb.org/extlink&oid=77888426&loc=SL77918673-209980 + Details
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- Definition Rental expense for the reporting period incurred under operating leases, including minimum and any contingent rent expense, net of related sublease income. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 840 -SubTopic 20 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=77902758&loc=d3e41499-112717 + Details
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