Amount of impairment loss from capitalized computer software costs.

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The amount of expense recognized in the current period that reflects the allocation of the cost of tangible assets over the assets' useful lives. Includes production and non-production related depreciation.

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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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Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

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Property and Equipment, net - Narrative (Details) - USD ($) $ in Millions	12 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2018
Property, Plant and Equipment [Line Items]
Depreciation expense	$ 13.3	$ 11.2	$ 9.4
Impairment charges	$ 5.7
Minimum [Member]
Property, Plant and Equipment [Line Items]
Property plant and equipment, useful life	3 years
Maximum [Member]
Property, Plant and Equipment [Line Items]
Property plant and equipment, useful life	10 years