CONSOLIDATED CONDENSED STATEMENTS OF CASH FLOWS (Parenthetical) (USD $) In Thousands, unless otherwise specified	9 Months Ended
Sep. 30, 2012	Sep. 30, 2011
CONSOLIDATED CONDENSED STATEMENTS OF CASH FLOWS
Dealership acquisitions net, repayment of sellers' floor plan notes payable	$ 49,467	$ 54,453

Repayment of sellers' floor plan notes payable, dealership acquisitions.

No definition available.

Name:	pag_RepaymentOfSellersFloorPlanNotesPayableDealershipAcquisitions
Namespace Prefix:	pag_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration