Long-Term Debt Revolving Loan (Details) (USD $)	12 Months Ended								12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2013 Revolving Credit Facility [Member]	Dec. 31, 2011 Revolving Credit Facility [Member]	Dec. 31, 2012 Revolving Credit Facility [Member]	Jun. 24, 2011 Revolving Credit Facility [Member]	Dec. 31, 2013 Letter of Credit [Member]	Dec. 31, 2013 Term Loan [Member]	Jul. 31, 2013 Term Loan [Member]	Dec. 31, 2012 Term Loan [Member]	Dec. 31, 2013 Higher Utilization [Member] Revolving Credit Facility [Member]	Dec. 31, 2013 Lower Utilization [Member] Revolving Credit Facility [Member]	Dec. 31, 2013 LIBOR [Member] Term Loan [Member]	Dec. 31, 2013 LIBOR [Member] Minimum [Member] Revolving Credit Facility [Member]	Dec. 31, 2013 LIBOR [Member] Minimum [Member] Term Loan [Member]	Apr. 29, 2013 LIBOR [Member] Minimum [Member] Term Loan [Member]	Dec. 31, 2013 LIBOR [Member] Maximum [Member] Revolving Credit Facility [Member]	Dec. 31, 2013 LIBOR [Member] Maximum [Member] Term Loan [Member]	Dec. 31, 2013 ABR [Member] Minimum [Member] Revolving Credit Facility [Member]	Dec. 31, 2013 ABR [Member] Minimum [Member] Term Loan [Member]	Dec. 31, 2013 ABR [Member] Maximum [Member] Revolving Credit Facility [Member]	Dec. 31, 2013 ABR [Member] Maximum [Member] Term Loan [Member]	Dec. 31, 2013 Accounts Payable, Inventory Financing [Member]	Dec. 31, 2013 Accounts Payable, Inventory Financing [Member]
Debt Instrument [Line Items]
Debt, long-term and short-term	$ 3,251,400,000			$ 0		$ 0			$ 1,528,900,000		$ 1,339,500,000
Letters of Credit Outstanding, Amount								2,200,000
Floorplan sub-facility, reserve				256,700,000																				9,900,000
Line of Credit Facility, Maximum Borrowing Capacity				900,000,000
Line of Credit Facility, Fee on Unused Portion, Basis Points				25								37.5	50
Gains (Losses) on Extinguishment of Debt	64,000,000	17,200,000	118,900,000		1,600,000				10,300,000
Deferred Finance Costs, Net							7,200,000			6,100,000
Amount owed under Revolving loan financing agreement																								246,800,000
Floorplan sub-facility, variation in balance due to timing																									9,300,000
Variable Interest Rate Margin, ABR Determination, Basis Point Plus Federal Funds Effective Rate				50
Variable Interest Rate Margin, ABR Determination, Percentage Plus LIBOR				1.00%
Variable Interest Rate Margin														3.25%	2.00%	2.25%	2.25%	2.50%	2.50%	1.00%	1.25%	1.50%	1.50%
Potential Margin Reduction				0.25%
Senior Secured Leverage Ratio, Maximum to Achieve Potential Margin Reduction				3.0
Percentage reserve for open orders under financing agreement				15.00%
Line of Credit Facility, Borrowing Base				1,065,500,000
Line of Credit Facility, Remaining Borrowing Capacity				$ 641,100,000
Revolving Loan, Consecutive Business Days Below Minimum Average Daily Excess Cash Availability Requirement				5 days
Revolving Loan, Minimum Average Daily Excess Cash Availability Requirement, Consecutive Business Days Met				30 days