Segment Information - Sales by Deliverable Type (Details) - USD ($) $ in Thousands	3 Months Ended
Dec. 31, 2020	Dec. 31, 2019
Disaggregation of Revenue
Sales	$ 318,794	$ 328,839
Products
Disaggregation of Revenue
Sales	181,489	200,604
Services
Disaggregation of Revenue
Sales	137,305	128,235
Cubic Transportation Systems
Disaggregation of Revenue
Sales	197,100	188,600
Cubic Transportation Systems \| Products
Disaggregation of Revenue
Sales	100,100	93,400
Cubic Transportation Systems \| Services
Disaggregation of Revenue
Sales	97,000	95,200
Cubic Mission and Performance Solutions
Disaggregation of Revenue
Sales	121,700	140,200
Cubic Mission and Performance Solutions \| Products
Disaggregation of Revenue
Sales	81,400	107,200
Cubic Mission and Performance Solutions \| Services
Disaggregation of Revenue
Sales	$ 40,300	$ 33,000

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.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
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-Name Accounting Standards Codification
-Topic 924
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+ Details