Consolidating Condensed Financial Information (Details 2) (USD $) In Thousands	6 Months Ended
Jun. 30, 2011	Jun. 30, 2010
CONSOLIDATING CONDENSED STATEMENT OF CASH FLOWS
Net cash from continuing operating activities	$ 43,990	$ 57,526
Investing activities:
Purchase of equipment and improvements	(51,784)	(35,989)
Dealership acquisitions, net, including repayment of sellers' floor plan notes payable of $5,862 and $5,683, respectively	(14,011)	(9,362)
Other	2,865
Net cash from continuing investing activities	(62,930)	(45,351)
Financing activities:
Repurchase of 3.5% senior subordinated convertible notes	(87,278)	(113,604)
Net borrowings (repayments) of other long-term debt	15,372	(9,497)
Net borrowings (repayments) of floor plan notes payable - non-trade	70,311	73,592
Proceeds from exercises of options, including excess tax benefit	2,698	211
Repurchases of common stock	(12,413)
Dividends	(6,493)
Net cash from continuing financing activities	(17,803)	(21,298)
Net cash from discontinued operations	22,221	12,717
Net change in cash and cash equivalents	(14,522)	3,594
Cash and cash equivalents, beginning of period	17,868	14,584
Cash and cash equivalents, end of period	3,346	18,178
Penske Automotive Group [Member]
CONSOLIDATING CONDENSED STATEMENT OF CASH FLOWS
Net cash from continuing operating activities	84,594	55,493
Investing activities:
Purchase of equipment and improvements	(1,308)
Net cash from continuing investing activities	(1,308)
Financing activities:
Repurchase of 3.5% senior subordinated convertible notes	(87,278)	(113,604)
Net borrowings (repayments) of other long-term debt		28,000
Net borrowings (repayments) of floor plan notes payable - non-trade	20,200	29,900
Proceeds from exercises of options, including excess tax benefit	2,698	211
Repurchases of common stock	(12,413)
Dividends	(6,493)
Net cash from continuing financing activities	(83,286)	(55,493)
Cash and cash equivalents, beginning of period	0
Cash and cash equivalents, end of period	0
Guarantor Subsidiaries [Member]
CONSOLIDATING CONDENSED STATEMENT OF CASH FLOWS
Net cash from continuing operating activities	5,591	(35,703)
Investing activities:
Purchase of equipment and improvements	(27,754)	(26,176)
Dealership acquisitions, net, including repayment of sellers' floor plan notes payable of $5,862 and $5,683, respectively	(12,331)	(9,362)
Other		83
Net cash from continuing investing activities	(40,085)	(35,455)
Financing activities:
Net borrowings (repayments) of other long-term debt	23,215	7,739
Net borrowings (repayments) of floor plan notes payable - non-trade	(30,056)	51,354
Distributions from (to) parent	4,245	473
Net cash from continuing financing activities	(2,596)	59,566
Net cash from discontinued operations	22,221	12,717
Net change in cash and cash equivalents	(14,869)	1,125
Cash and cash equivalents, beginning of period	15,497	12,929
Cash and cash equivalents, end of period	1,455	14,054
Non-Guarantor Subsidiaries [Member]
CONSOLIDATING CONDENSED STATEMENT OF CASH FLOWS
Net cash from continuing operating activities	(46,195)	37,736
Investing activities:
Purchase of equipment and improvements	(22,722)	(9,813)
Dealership acquisitions, net, including repayment of sellers' floor plan notes payable of $5,862 and $5,683, respectively	(1,680)
Other	2,865	(83)
Net cash from continuing investing activities	(21,537)	(9,896)
Financing activities:
Net borrowings (repayments) of other long-term debt	(7,843)	(17,236)
Net borrowings (repayments) of floor plan notes payable - non-trade	80,167	(7,662)
Distributions from (to) parent	(4,245)	(473)
Net cash from continuing financing activities	68,079	(25,371)
Net change in cash and cash equivalents	347	2,469
Cash and cash equivalents, beginning of period	2,371	1,655
Cash and cash equivalents, end of period	$ 1,891	$ 4,124

Distributions from (to) parent.

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The net (repayments) borrowings of floor plan notes payable to parties other than the manufacturer of the new vehicle and all floor plan notes payable related to pre-owned vehicles.

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The cash inflow associated with the amount received from holders exercising their stock options including cash inflow associated with reductions in the entity's income taxes that arise when compensation cost recognized on the entity's tax return exceeds compensation cost from share-based compensation recognized in financial statements.

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Includes currency on hand as well as demand deposits with banks or financial institutions. It also includes other kinds of accounts that have the general characteristics of demand deposits in that the Entity may deposit additional funds at any time and also effectively may withdraw funds at any time without prior notice or penalty. Cash equivalents, excluding items classified as marketable securities, include short-term, highly liquid investments that are both readily convertible to known amounts of cash, and so near their maturity that they present minimal risk of changes in value because of changes in interest rates. Generally, only investments with original maturities of three months or less qualify under that definition. Original maturity means original maturity to the entity holding the investment. For example, both a three-month US Treasury bill and a three-year Treasury note purchased three months from maturity qualify as cash equivalents. However, a Treasury note purchased three years ago does not become a cash equivalent when its remaining maturity is three months. Compensating balance arrangements that do not legally restrict the withdrawal or usage of cash amounts may be reported as Cash and Cash Equivalents, while legally restricted deposits held as compensating balances against borrowing arrangements, contracts entered into with others, or company statements of intention with regard to particular deposits should not be reported as cash and cash equivalents.

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The net change between the beginning and ending balance of cash and cash equivalents.

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Net change in cash associated with the entity's discontinued operations.

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The net cash from (used in) the entity's financing activities specifically EXCLUDING the cash flows derived by the entity from its discontinued operations, if any. This element is only to be used when the entity reports its cash flows attributable to discontinued operations separately from the cash flow provided by or used in financing activities. Such reporting would necessitate the entity to use the Net Cash Provided by (Used in) Discontinued Operations, Total element provided in the taxonomy.

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Cash generated by or used in financing activities of continuing operations; excludes cash flows from discontinued operations.

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The net cash from (used in) the entity's investing activities specifically EXCLUDING the cash flows derived by the entity from its discontinued operations, if any. This element is only to be used when the entity reports its cash flows attributable to discontinued operations separately from the cash flow provided by or used in investing activities. Such reporting would necessitate the entity to use the Net Cash Provided by (Used in) Discontinued Operations, Total element provided in the taxonomy.

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Cash generated by or used in investing activities of continuing operations; excludes cash flows from discontinued operations.

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The net cash from (used in) the entity's continuing operations. This element specifically EXCLUDES the cash flows derived by the entity from its discontinued operations, if any. This element is only to be used when the entity reports its cash flows attributable to discontinued operations separately from the cash flow provided by or used in operating activities.

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The net cash outflow (inflow) from other investing activities. This element is used when there is not a more specific and appropriate element in the taxonomy.

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The cash outflow to reacquire common stock during the period.

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The cash outflow from the distribution of an entity's earnings in the form of dividends to common shareholders.

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The cash outflow associated with the acquisition of a business, net of the cash acquired from the purchase.

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The cash outflow for purchases of and capital improvements on property, plant and equipment (capital expenditures), software, and other intangible assets.

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Net change in economic resources obtained through long-term financing, include net changes in Other Long-Term Debt not otherwise defined.

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The cash outflow from the repayment of debt instrument which can be exchanged for a specified amount of another security, typically the entity's common stock, at the option of the issuer or the holder.

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