Related Party Transactions (Details 2)	12 Months Ended
Dec. 31, 2014
Audi, Mercedes-Benz, Porsche, smart \| Fairfield, Connecticut
Related party transactions
Ownership percentage of Equity Method Investment	82.19%
Ownership percentage, option to purchase	20.00%
Audi, Mercedes-Benz, Porsche, smart \| Fairfield, Connecticut \| Lucio A. Noto
Related party transactions
Ownership percentage of Equity Method Investment	17.81%
Mercedes-Benz \| Greenwich, Connecticut
Related party transactions
Ownership percentage of Equity Method Investment	80.00%
Percentage of operating profit	20.00%
Mercedes-Benz \| Greenwich, Connecticut \| Lucio A. Noto
Related party transactions
Ownership percentage, option to purchase	20.00%
Ferrari, Maserati \| Las Vegas, Nevada
Related party transactions
Ownership percentage of Equity Method Investment	50.00%
Lexus Toyota Volkswagen \| Frankfurt, Germany
Related party transactions
Ownership percentage of Equity Method Investment	50.00%
Audi, Citroen, Kia, Maserati, SEAT, Skoda, Toyota, Volkswagen \| Aachen, Germany
Related party transactions
Ownership percentage of Equity Method Investment	50.00%
BMW, MINI, Maserati \| Northern Italy
Related party transactions
Ownership percentage of Equity Method Investment	70.00%
BMW,MINI \| Barcelona Spain
Related party transactions
Ownership percentage of Equity Method Investment	50.00%
Max Cycles
Related party transactions
Ownership percentage of Equity Method Investment	50.00%
Penske Commercial Leasing Australia
Related party transactions
Ownership percentage of Equity Method Investment	45.00%
Penske Vehicle Services
Related party transactions
Ownership percentage of Equity Method Investment	31.00%
National Powersport Auctions
Related party transactions
Ownership percentage of Equity Method Investment	7.00%
PCV US
Related party transactions
Ownership percentage of Consolidated Entity	91.00%
i.M. Branded
Related party transactions
Ownership percentage of Consolidated Entity	90.00%

The percentage of ownership of common stock or equity participation in a consolidated entity.

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- Definition

Represents the percentage of ownership interest available under option to purchase.

+ References

No definition available.

+ Details

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- Definition

Represents the percentage of operating profit entitled to investor based on his ownership interest.

+ References

No definition available.

+ Details

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- Definition

The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 323

-SubTopic 10

-Section 50

-Paragraph 3

-Subparagraph (a)(1)

-URI http://asc.fasb.org/extlink&oid=6382943&loc=d3e33918-111571

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