Condensed Consolidated Financial Information Condensed Consolidated Income Statement (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Condensed Income Statements, Captions [Line Items]
REVENUES:	$ 2,672,602	$ 2,800,569	$ 2,726,480	$ 2,432,854	$ 2,538,940	$ 2,626,448	$ 2,511,638	$ 2,260,863	$ 10,632,505	$ 9,937,889	$ 8,918,581
COST OF SALES:									9,098,533	8,489,951	7,626,035
GROSS PROFIT	380,133	398,382	391,573	$ 363,884	365,959	374,709	369,148	$ 338,122	1,533,972	1,447,938	1,292,546
SELLING, GENERAL AND ADMINISTRATIVE EXPENSES									1,120,833	1,061,964	976,856
Depreciation and amortization									47,239	42,344	35,826
ASSET IMPAIRMENTS	$ 85,700	$ 900	$ 1,000		$ 30,400	$ 9,400	$ 1,700		87,562	41,520	6,542
(LOSS) INCOME FROM OPERATIONS									278,338	302,110	273,322
Floorplan interest expense									(39,264)	(41,614)	(41,667)
Interest Expense, Other									(56,903)	(49,693)	(38,971)
Gains (Losses) on Extinguishment of Debt									0	(46,403)	0
Other Expenses									0	0	(789)
(LOSS) INCOME BEFORE INCOME TAXES AND EQUITY IN EARNINGS OF SUBSIDIARIES									182,171	164,400	191,895
BENEFIT (PROVISION) FOR INCOME TAXES									(88,172)	(71,396)	(77,903)
EQUITY IN EARNINGS OF SUBSIDIARIES									0	0	0
NET INCOME									93,999	93,004	113,992
COMPREHENSIVE LOSS									(56,000)	(30,307)	(18,620)
COMPREHENSIVE INCOME (LOSS) ATTRIBUTABLE TO PARENT									37,999	62,697	95,372
Parent Company [Member]
Condensed Income Statements, Captions [Line Items]
REVENUES:									0	0	0
COST OF SALES:									0	0	0
GROSS PROFIT									0	0	0
SELLING, GENERAL AND ADMINISTRATIVE EXPENSES									3,024	2,796	7,922
Depreciation and amortization									0	0	0
ASSET IMPAIRMENTS									0	0	0
(LOSS) INCOME FROM OPERATIONS									(3,024)	(2,796)	(7,922)
Floorplan interest expense									0	0	0
Interest Expense, Other									2,320	2,272	1,846
Gains (Losses) on Extinguishment of Debt										0
Other Expenses											0
(LOSS) INCOME BEFORE INCOME TAXES AND EQUITY IN EARNINGS OF SUBSIDIARIES									(704)	(524)	(6,076)
BENEFIT (PROVISION) FOR INCOME TAXES									264	196	2,277
EQUITY IN EARNINGS OF SUBSIDIARIES									94,439	93,332	117,791
NET INCOME									93,999	93,004	113,992
COMPREHENSIVE LOSS									0	0	0
COMPREHENSIVE INCOME (LOSS) ATTRIBUTABLE TO PARENT									93,999	93,004	113,992
Guarantor Subsidiaries [Member]
Condensed Income Statements, Captions [Line Items]
REVENUES:									8,893,990	8,175,242	7,353,340
COST OF SALES:									7,555,043	6,929,334	6,236,925
GROSS PROFIT									1,338,947	1,245,908	1,116,415
SELLING, GENERAL AND ADMINISTRATIVE EXPENSES									950,268	883,442	817,907
Depreciation and amortization									41,220	36,701	31,670
ASSET IMPAIRMENTS									18,899	15,571	6,542
(LOSS) INCOME FROM OPERATIONS									328,560	310,194	260,296
Floorplan interest expense									(36,063)	(34,061)	(33,789)
Interest Expense, Other									(52,276)	(46,517)	(37,982)
Gains (Losses) on Extinguishment of Debt										(46,403)
Other Expenses											0
(LOSS) INCOME BEFORE INCOME TAXES AND EQUITY IN EARNINGS OF SUBSIDIARIES									240,221	183,213	188,525
BENEFIT (PROVISION) FOR INCOME TAXES									(89,698)	(77,911)	(73,092)
EQUITY IN EARNINGS OF SUBSIDIARIES									0	0	0
NET INCOME									150,523	105,302	115,433
COMPREHENSIVE LOSS									(1,543)	(4,059)	13,081
COMPREHENSIVE INCOME (LOSS) ATTRIBUTABLE TO PARENT									148,980	101,243	128,514
Non-Guarantor Subsidiaries [Member]
Condensed Income Statements, Captions [Line Items]
REVENUES:									1,738,515	1,762,647	1,565,241
COST OF SALES:									1,543,490	1,560,617	1,389,110
GROSS PROFIT									195,025	202,030	176,131
SELLING, GENERAL AND ADMINISTRATIVE EXPENSES									167,541	175,726	151,027
Depreciation and amortization									6,019	5,643	4,156
ASSET IMPAIRMENTS									68,663	25,949	0
(LOSS) INCOME FROM OPERATIONS									(47,198)	(5,288)	20,948
Floorplan interest expense									(3,201)	(7,553)	(7,878)
Interest Expense, Other									(6,947)	(5,448)	(2,835)
Gains (Losses) on Extinguishment of Debt										0
Other Expenses											(789)
(LOSS) INCOME BEFORE INCOME TAXES AND EQUITY IN EARNINGS OF SUBSIDIARIES									(57,346)	(18,289)	9,446
BENEFIT (PROVISION) FOR INCOME TAXES									1,262	6,319	(7,088)
EQUITY IN EARNINGS OF SUBSIDIARIES									0	0	0
NET INCOME									(56,084)	(11,970)	2,358
COMPREHENSIVE LOSS									(54,457)	(26,248)	(31,701)
COMPREHENSIVE INCOME (LOSS) ATTRIBUTABLE TO PARENT									(110,541)	(38,218)	(29,343)
Consolidation, Eliminations [Member]
Condensed Income Statements, Captions [Line Items]
REVENUES:									0	0	0
COST OF SALES:									0	0	0
GROSS PROFIT									0	0	0
SELLING, GENERAL AND ADMINISTRATIVE EXPENSES									0	0	0
Depreciation and amortization									0	0	0
ASSET IMPAIRMENTS									0	0	0
(LOSS) INCOME FROM OPERATIONS									0	0	0
Floorplan interest expense									0	0	0
Interest Expense, Other									0	0	0
Gains (Losses) on Extinguishment of Debt										0
Other Expenses											0
(LOSS) INCOME BEFORE INCOME TAXES AND EQUITY IN EARNINGS OF SUBSIDIARIES									0	0	0
BENEFIT (PROVISION) FOR INCOME TAXES									0	0	0
EQUITY IN EARNINGS OF SUBSIDIARIES									(94,439)	(93,332)	(117,791)
NET INCOME									(94,439)	(93,332)	(117,791)
COMPREHENSIVE LOSS									0	0	0
COMPREHENSIVE INCOME (LOSS) ATTRIBUTABLE TO PARENT									$ (94,439)	$ (93,332)	$ (117,791)