Interim Financial Statements (Details)	3 Months Ended
Mar. 31, 2013 item
Interim Financial Statements
Total number of owned and operated franchises	342
Number of owned and operated franchises in US	174
Number of owned and operated franchises outside US	168
Minimum number of on and off-airport locations in which company operates	50
Significant Accounting Policies
Percentage of holding in Italian automotive retail joint venture sold	50.00%
Ownership interest in the voting stock of the affiliate (as a percent)	35.00%
Penske Truck Leasing Co., L.P.
Significant Accounting Policies
Ownership interest in Penske Truck Leasing Co (as a percent)	9.00%

Represents the minimum number of on and off-airport locations in which company operates.

No definition available.

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- Definition

Total number of owned and operated franchises.

+ References

No definition available.

+ Details

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- Definition

Number of owned and operated franchises in domestic country.

+ References

No definition available.

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- Definition

Number of owned and operated franchises in foreign countries.

+ References

No definition available.

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- Definition

Represents the percentage of holdings in joint venture sold during the period.

+ 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 Statement of Financial Accounting Standard (FAS)

-Number 159

-Paragraph 18

-Subparagraph f

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: 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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-Publisher AICPA

-Name Accounting Principles Board Opinion (APB)

-Number 18

-Paragraph 20

-Subparagraph a (1)

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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- Definition

The number of units or percentage investment held in the subsidiary by the limited liability company or limited partnership.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 22

-Article 12

+ Details

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