REPORTING SEGMENTS - Reconciliation to Net Income (Loss) (Details) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2019 USD ($)	Jun. 30, 2018 USD ($)	Jun. 30, 2019 USD ($) segment	Jun. 30, 2018 USD ($)
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Number of reporting segments included in operating component | segment			3
Total revenues	$ 1,265,426	$ 980,828	$ 2,190,518	$ 1,733,161
Gross margin	233,774	178,711	405,814	321,813
Selling, general and administrative expenses	(124,817)	(100,065)	(228,700)	(187,080)
Equity in (loss)/income of unconsolidated entities	3,561	4,017	5,880	7,263
Interest and other (expense)/income, net	(2,499)	(3,378)	(4,903)	(3,473)
Income/(loss) before income taxes	110,019	79,285	178,091	138,523
Operating Segments | East
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Total revenues	485,376	360,472	840,328	645,279
Gross margin	77,149	65,128	138,325	117,417
Selling, general and administrative expenses	(41,459)	(31,105)	(77,018)	(59,738)
Equity in (loss)/income of unconsolidated entities	0	128	0	239
Interest and other (expense)/income, net	(1,924)	(122)	(3,537)	(600)
Income/(loss) before income taxes	33,766	34,029	57,770	57,318
Operating Segments | Central
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Total revenues	363,003	298,112	617,950	512,224
Gross margin	62,649	53,653	104,993	94,280
Selling, general and administrative expenses	(31,297)	(26,122)	(57,561)	(48,402)
Equity in (loss)/income of unconsolidated entities	(82)	374	(171)	755
Interest and other (expense)/income, net	251	(130)	(556)	(238)
Income/(loss) before income taxes	31,521	27,775	46,705	46,395
Operating Segments | West
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Total revenues	394,228	305,978	693,377	545,186
Gross margin	84,202	54,816	147,399	100,840
Selling, general and administrative expenses	(24,976)	(20,061)	(45,540)	(35,626)
Equity in (loss)/income of unconsolidated entities	1,735	1,476	2,556	2,571
Interest and other (expense)/income, net	178	(101)	(211)	(81)
Income/(loss) before income taxes	61,139	36,130	104,204	67,704
Operating Segments | Financial Services
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Total revenues	22,819	16,266	38,863	30,472
Gross margin	9,774	5,114	15,097	9,276
Selling, general and administrative expenses	0	0	0	0
Equity in (loss)/income of unconsolidated entities	1,926	2,039	3,335	3,698
Interest and other (expense)/income, net	0	0	0	0
Income/(loss) before income taxes	11,700	7,153	18,432	12,974
Corporate and Unallocated
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Total revenues	0	0	0	0
Gross margin	0	0	0	0
Selling, general and administrative expenses	(27,085)	(22,777)	(48,581)	(43,314)
Equity in (loss)/income of unconsolidated entities	(18)	0	160	0
Interest and other (expense)/income, net	(1,004)	(3,025)	(599)	(2,554)
Income/(loss) before income taxes	$ (28,107)	$ (25,802)	$ (49,020)	$ (45,868)