CONSOLIDATED CONDENSED STATEMENTS OF INCOME (USD $) In Millions, except Per Share data, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Revenue:
Total revenues	$ 4,471.1us-gaap_SalesRevenueNet	$ 4,015.2us-gaap_SalesRevenueNet
Cost of sales:
Total cost of sales	3,782.4us-gaap_CostOfGoodsAndServicesSold	3,401.2us-gaap_CostOfGoodsAndServicesSold
Gross profit	688.7us-gaap_GrossProfit	614.0us-gaap_GrossProfit
Selling, general and administrative expenses	534.5	477.2
Depreciation	18.6us-gaap_Depreciation	16.1us-gaap_Depreciation
Operating income	135.6us-gaap_OperatingIncomeLoss	120.7us-gaap_OperatingIncomeLoss
Floor plan interest expense	(10.1)pag_FloorPlanInterestExpense	(11.1)pag_FloorPlanInterestExpense
Other interest expense	(16.3)	(12.4)
Equity in earnings of affiliates	6.7	5.1
Income from continuing operations before income taxes	115.9	102.3
Income taxes	(38.8)us-gaap_IncomeTaxExpenseBenefit	(34.7)us-gaap_IncomeTaxExpenseBenefit
Income from continuing operations	77.1	67.6
Income (loss) from discontinued operations, net of tax	(1.2)	0.3
Net income	75.9us-gaap_ProfitLoss	67.9us-gaap_ProfitLoss
Less: Income attributable to non-controlling interests	0.7	0.4
Net income attributable to Penske Automotive Group common stockholders	75.2us-gaap_NetIncomeLoss	67.5us-gaap_NetIncomeLoss
Basic earnings per share attributable to Penske Automotive Group common stockholders:
Continuing operations (in dollars per share)	$ 0.85	$ 0.74
Discontinued operations (in dollars per share)	$ (0.01)	$ 0.00
Net income attributable to Penske Automotive Group common stockholders (in dollars per share)	$ 0.83us-gaap_EarningsPerShareBasic	$ 0.75us-gaap_EarningsPerShareBasic
Shares used in determining basic earnings per share (Note 6) (in shares)	90.3	90.4
Diluted earnings per share attributable to Penske Automotive Group common stockholders:
Continuing operations (in dollars per share)	$ 0.85	$ 0.74
Discontinued operations (in dollars per share)	$ (0.01)	$ 0.00
Net income attributable to Penske Automotive Group common stockholders (in dollars per share)	$ 0.83us-gaap_EarningsPerShareDiluted	$ 0.75us-gaap_EarningsPerShareDiluted
Shares used in determining diluted earnings per share (Note 6) (in shares)	90.3	90.5
Amounts attributable to Penske Automotive Group common stockholders:
Income from continuing operations	77.1	67.6
Less: Income attributable to non-controlling interests	0.7	0.4
Income from continuing operations, net of tax	76.4	67.2
Income (loss) from discontinued operations, net of tax	(1.2)	0.3
Net income attributable to Penske Automotive Group common stockholders	75.2us-gaap_NetIncomeLoss	67.5us-gaap_NetIncomeLoss
Retail Automotive Dealership
Revenue:
Total revenues	4,175.0	3,919.2
Cost of sales:
Total cost of sales	3,546.9	3,321.5
Retail Commercial Truck Dealership
Revenue:
Total revenues	192.7
Cost of sales:
Total cost of sales	159.9
Commercial Vehicle Distribution And Other
Revenue:
Total revenues	103.4	96.0
Cost of sales:
Total cost of sales	$ 75.6	$ 79.7

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

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The consolidated profit or loss for the period, net of income taxes, including the portion attributable to the noncontrolling interest.

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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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The aggregate total costs related to selling a firm's product and services, as well as all other general and administrative expenses. Direct selling expenses (for example, credit, warranty, and advertising) are expenses that can be directly linked to the sale of specific products. Indirect selling expenses are expenses that cannot be directly linked to the sale of specific products, for example telephone expenses, Internet, and postal charges. General and administrative expenses include salaries of non-sales personnel, rent, utilities, communication, etc.

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-SubTopic 10

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The average number of shares or units issued and outstanding that are used in calculating diluted EPS or earnings per unit (EPU), determined based on the timing of issuance of shares or units in the period.

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Number of [basic] shares or units, after adjustment for contingently issuable shares or units and other shares or units not deemed outstanding, determined by relating the portion of time within a reporting period that common shares or units have been outstanding to the total time in that period.

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