Revenue Recognition - Additional Information (Details)	3 Months Ended
Dec. 31, 2019 USD ($) Segment Customer	Dec. 31, 2018 USD ($) Customer
Disaggregation Of Revenue [Line Items]
Number of reportable segments \| Segment	1
Revenues	$ 77,459,000	$ 72,484,000
Contract acquisition costs	2,100,000
Contract acquisition cost, amortization	200,000
Contract acquisition cost, impairment	0
Capitalized contract cost, net	43,000,000
Capitalized contract cost, amortization	2,700,000
Capitalized contract cost, impairment	0
Customer One
Disaggregation Of Revenue [Line Items]
Revenues	18,000,000	13,500,000
Customer Two
Disaggregation Of Revenue [Line Items]
Revenues		8,100,000
United States
Disaggregation Of Revenue [Line Items]
Revenues	35,041,000	38,064,000
Germany
Disaggregation Of Revenue [Line Items]
Revenues	20,217,000	13,716,000
Japan
Disaggregation Of Revenue [Line Items]
Revenues	$ 11,411,000	$ 9,753,000
Revenues \| Customer Concentration Risk
Disaggregation Of Revenue [Line Items]
Number of customers accounted for revenues \| Customer	1	2
Revenues \| Customer Concentration Risk \| Customer One
Disaggregation Of Revenue [Line Items]
Percentage of revenue	23.20%	18.70%
Revenues \| Customer Concentration Risk \| Customer Two
Disaggregation Of Revenue [Line Items]
Percentage of revenue		11.20%
Minimum
Disaggregation Of Revenue [Line Items]
Connected services contract term	1 year
Contract acquisition cost, deferred and amortized over benefit period	1 year
Contract term	1 year
Minimum \| Revenues \| United States \| Geographic Concentration Risk
Disaggregation Of Revenue [Line Items]
Percentage of revenue	10.00%	10.00%
Minimum \| Revenues \| Germany \| Geographic Concentration Risk
Disaggregation Of Revenue [Line Items]
Percentage of revenue	10.00%	10.00%
Minimum \| Revenues \| Japan \| Geographic Concentration Risk
Disaggregation Of Revenue [Line Items]
Percentage of revenue	10.00%	10.00%
Maximum
Disaggregation Of Revenue [Line Items]
Connected services contract term	5 years
Contract acquisition costs, expected benefit period	1 year
Contract acquisition cost, deferred and amortized over benefit period	5 years
Contract term	5 years

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Contract acquisition cost, amortization.

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Contract acquisition cost, deferred and amortized over benefit period.

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Contract acquisition cost, impairment.

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Contract acquisition costs.

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Contract acquisition costs, expected benefit period.

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Number of customers accounted for revenues.

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Amount of amortization expense for asset recognized from cost incurred to obtain or fulfill contract with customer.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 340
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-Paragraph 3
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Amortization period of cost capitalized in obtaining or fulfilling contract with customer, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
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Amount of impairment loss for asset recognized from cost incurred to obtain or fulfill contract with customer.

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Amount, after accumulated amortization and accumulated impairment loss, of asset recognized from cost incurred to obtain or fulfill contract with customer.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

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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.

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Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements.

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Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
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