The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

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Amount of expense for amortization of capitalized computer software costs.

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Useful life of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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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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Software and Other Intangible Assets - Additional Information (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Finite-Lived Intangible Assets [Line Items]
Other intangible assets amortization expense	$ 9.3	$ 9.4	$ 27.8	$ 22.5
Software for resale
Finite-Lived Intangible Assets [Line Items]
Software, amortization expense	2.1	2.8	6.1	8.8
Software for internal use
Finite-Lived Intangible Assets [Line Items]
Software, amortization expense	$ 17.9	$ 15.7	$ 53.1	$ 39.4
Minimum \| Software for resale
Finite-Lived Intangible Assets [Line Items]
Finite-lived intangible asset, useful life (in years)			5 years
Minimum \| Software for internal use
Finite-Lived Intangible Assets [Line Items]
Finite-lived intangible asset, useful life (in years)			1 year
Maximum \| Software for resale
Finite-Lived Intangible Assets [Line Items]
Finite-lived intangible asset, useful life (in years)			10 years
Maximum \| Software for internal use
Finite-Lived Intangible Assets [Line Items]
Finite-lived intangible asset, useful life (in years)			10 years