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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Amount before accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

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Property and Equipment, net - Narrative (Details) - USD ($) $ in Millions	12 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2019
Property, Plant and Equipment [Line Items]
Depreciation expense	$ 21.3	$ 13.3	$ 11.2
Total property and equipment	$ 155.3	107.9
Impairment charges		5.7
Capitalized software development
Property, Plant and Equipment [Line Items]
Property plant and equipment, useful life	3 years
Total property and equipment	$ 22.3	$ 0.0
Minimum
Property, Plant and Equipment [Line Items]
Property plant and equipment, useful life	3 years
Maximum
Property, Plant and Equipment [Line Items]
Property plant and equipment, useful life	10 years