Segment Information - Additional Information (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Segment Reporting Information [Line Items]
Profit included in operating income	$ 40.8	$ (8.5)	$ 84.4	$ 11.6
ECS \| Hardware and Software \| Segment Reconciling Items
Segment Reporting Information [Line Items]
Profit included in operating income	$ 0.4	$ 0.0	$ 1.1	$ 0.0

The net result for the period of deducting operating expenses from operating revenues.

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