Divestitures [Abstract]

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The percentage of ownership interest sold in the investment.

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Represents the number of dealerships disposed of by the entity during the period.

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Represents the number of entities newly classified as held for sale.

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Represents the number of franchises disposed of by the entity during the period.

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The number of franchises transitioned during the period to another existing franchise.

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Represents the number of locations disposed of by the entity during the period.

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Amount before tax of income (loss) from a discontinued operation. Includes, but is not limited to, the income (loss) from operations during the phase-out period, gain (loss) on disposal, gain (loss) for reversal of write-down (write-down) to fair value, less cost to sell, and adjustments to a prior period gain (loss) on disposal.

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Amount classified as other liabilities attributable to disposal group held for sale or disposed of, expected to be disposed of within one year or the normal operating cycle, if longer.

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Amount of revenue attributable to disposal group, including, but not limited to, discontinued operation.

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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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Amount classified as liabilities attributable to disposal group held for sale or disposed of, expected to be disposed of within one year or the normal operating cycle, if longer.

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Discontinued Operations and Divestitures (Details) $ in Millions	1 Months Ended	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2018 USD ($) entity item	Dec. 31, 2017 USD ($) entity item	Dec. 31, 2016 USD ($) entity item
Discontinued Operations and Divestitures
Number of entities newly classified as held for sale \| entity		0	0	0
Balance Sheet information regarding entities accounted for as discontinued operations
Total liabilities \| $		$ 0.7	$ 0.7
Held-for-sale
Combined financial information regarding entities accounted for as discontinued operations
Revenues \| $			2.1	$ 24.8
Pre-tax loss \| $		0.6	(0.4)	$ (1.7)
Balance Sheet information regarding entities accounted for as discontinued operations
Other liabilities \| $		0.7	0.7
Total liabilities \| $		$ 0.7	$ 0.7
Disposed of by sale - Discontinued Operations
Divestitures
Number of franchises disposed			1
Disposed of by sale - Continuing Operations \| i.M. Branded
Divestitures
Ownership interest sold in previous consolidated entity (as a percent)	90.00%
Disposal group, not discontinued operations
Divestitures
Number of franchises disposed			24
Retail Automotive Franchise
Divestitures
Number of franchises disposed		7	25	10
Number of franchises transitioned from Scion brand to existing Toyota franchises				17
Retail Commercial Truck Dealership
Divestitures
Number of dealerships disposed		1		1
Retail Commercial Truck Parts Location
Divestitures
Number of locations disposed				1