Segment Information - Reportable Segment Revenue, Income (Loss) Before Income Taxes, (Provision) Benefit for Income Taxes and Net Income (Loss) (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Segment Reporting Information [Line Items]
Revenues	$ 2,690.8	$ 2,808.4
Income (loss) before income taxes	38.9	52.2
Severance expense	0.9
U.S.
Segment Reporting Information [Line Items]
Revenues	2,007.6	2,062.8
Income (loss) before income taxes	42.2	46.4
Gain on real estate and dealership transactions		5.2
Asset impairments		2.0
U.S. and Brazil
Segment Reporting Information [Line Items]
Loss on legal matters		2.4
U.K.
Segment Reporting Information [Line Items]
Revenues	590.7	642.2
Income (loss) before income taxes	(2.7)	6.2
Brazil
Segment Reporting Information [Line Items]
Revenues	92.5	103.4
Income (loss) before income taxes	$ (0.6)	$ (0.4)

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Amount of gain (loss) recognized in settlement of litigation and insurance claims. Excludes claims within an insurance entity's normal claims settlement process.

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