Acquisitions - Summary of Fair Value as of Acquisition Date (Details) $ in Thousands	12 Months Ended
Sep. 30, 2019 USD ($)
Vergokan
Business Acquisition [Line Items]
Intangible assets	$ 12,621
Other
Business Acquisition [Line Items]
Intangible assets	16,400
Customer relationships \| Vergokan
Business Acquisition [Line Items]
Fair Value	$ 10,535
Weighted Average Useful Life (Years)	12 years
Customer relationships \| Other
Business Acquisition [Line Items]
Fair Value	$ 15,400
Weighted Average Useful Life (Years)	10 years
Other \| Vergokan
Business Acquisition [Line Items]
Fair Value	$ 2,086
Weighted Average Useful Life (Years)	9 years
Other \| Other
Business Acquisition [Line Items]
Fair Value	$ 1,000
Weighted Average Useful Life (Years)	9 years

Weighted average amortization period of finite-lived intangible assets acquired either individually or as part of a group of assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (a)(3)
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- Definition

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.

+ References

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- Definition

The amount of identifiable intangible assets recognized as of the acquisition date.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 55
-Paragraph 37
-URI http://asc.fasb.org/extlink&oid=121600890&loc=d3e2207-128464

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
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- Definition

Amount of increase in assets, excluding financial assets, lacking physical substance with a definite life, from an acquisition.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 1
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