Number of geographic operating segments.

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Amount of income (loss) from continuing operations, including income (loss) from equity method investments, before deduction of income tax expense (benefit), and income (loss) attributable to noncontrolling interest.

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-Publisher FASB
-Name Accounting Standards Codification
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-Name Accounting Standards Codification
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Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements.

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No definition available.

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Total revenue from sale of goods and services rendered during the reporting period, in the normal course of business, reduced by sales returns and allowances, and sales discounts.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
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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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Segment Information (Details) $ in Millions	3 Months Ended		9 Months Ended		12 Months Ended
Segment Information (Details) $ in Millions	Sep. 30, 2016 USD ($)	Sep. 30, 2015 USD ($)	Sep. 30, 2016 USD ($) item	Sep. 30, 2015 USD ($)	Dec. 31, 2015 USD ($)
Segment Reporting Information
Number of reportable Segments \| item			3
Number of geographic operating segments \| item			4
Revenues and segment income by reportable segment
Revenues	$ 5,152.0	$ 4,960.1	$ 15,230.7	$ 14,363.6
Segment income	130.1	129.3	393.2	388.4
Intersegment Elimination
Revenues and segment income by reportable segment
Revenues	(0.9)	(0.5)	(2.6)	(1.1)
Retail Automotive Dealership
Revenues and segment income by reportable segment
Revenues	4,772.1	4,585.8	14,121.8	13,327.5	$ 17,900.0
Retail Automotive Dealership \| Operating segments
Revenues and segment income by reportable segment
Revenues	4,772.1	4,585.8	14,121.8	13,327.5
Segment income	97.2	107.8	330.7	330.9
Retail Commercial Truck Dealership
Revenues and segment income by reportable segment
Revenues	266.1	268.5	782.3	703.1
Retail Commercial Truck Dealership \| Operating segments
Revenues and segment income by reportable segment
Revenues	266.1	268.5	782.3	703.1
Segment income	8.4	10.3	21.8	28.1
Other \| Operating segments
Revenues and segment income by reportable segment
Revenues	114.7	106.3	329.2	334.1
Segment income	$ 24.5	$ 11.2	$ 40.7	$ 29.4