Segment Disclosures - Profit before Taxes (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Segment Reporting Reconciling Item For Operating Profit Loss From Segment To Consolidated [Line Items]
Profit before taxes	$ 185,003	$ 184,996	$ 433,035	$ 396,043
Equity-based compensation expense			(32,459)	(39,874)
Corporate interest expense	(5,624)	(6,081)	(15,526)	(17,955)
Homebuilding [Member]
Segment Reporting Reconciling Item For Operating Profit Loss From Segment To Consolidated [Line Items]
Profit before taxes	167,657	168,874	392,839	362,706
Corporate interest expense	(5,338)	(5,900)	(14,734)	(17,499)
Mortgage Banking [Member]
Segment Reporting Reconciling Item For Operating Profit Loss From Segment To Consolidated [Line Items]
Profit before taxes	17,346	16,122	40,196	33,337
Corporate interest expense	(286)	(181)	(792)	(456)
Operating Segments [Member]
Segment Reporting Reconciling Item For Operating Profit Loss From Segment To Consolidated [Line Items]
Profit before taxes	159,250	163,099	384,980	374,290
Operating Segments [Member] | Homebuilding [Member] | Mid Atlantic [Member]
Segment Reporting Reconciling Item For Operating Profit Loss From Segment To Consolidated [Line Items]
Profit before taxes	81,137	88,058	191,476	217,665
Operating Segments [Member] | Homebuilding [Member] | North East [Member]
Segment Reporting Reconciling Item For Operating Profit Loss From Segment To Consolidated [Line Items]
Profit before taxes	8,711	10,745	18,354	29,359
Operating Segments [Member] | Homebuilding [Member] | Mid East [Member]
Segment Reporting Reconciling Item For Operating Profit Loss From Segment To Consolidated [Line Items]
Profit before taxes	34,699	29,958	87,488	52,607
Operating Segments [Member] | Homebuilding [Member] | South East [Member]
Segment Reporting Reconciling Item For Operating Profit Loss From Segment To Consolidated [Line Items]
Profit before taxes	16,548	17,372	45,159	38,812
Operating Segments [Member] | Mortgage Banking [Member]
Segment Reporting Reconciling Item For Operating Profit Loss From Segment To Consolidated [Line Items]
Profit before taxes	18,155	16,966	42,503	35,847
Reconciling Items [Member]
Segment Reporting Reconciling Item For Operating Profit Loss From Segment To Consolidated [Line Items]
Profit before taxes	25,753	21,897	48,055	21,753
Contract land deposit reserve adjustment	785	4,705	3,421	11,511
Equity-based compensation expense	(11,081)	(13,571)	(32,459)	(39,874)
Corporate capital allocation	50,032	45,690	140,606	124,033
Unallocated corporate overhead	(18,459)	(18,055)	(74,485)	(67,803)
Consolidation adjustments and other	9,798	9,147	25,660	11,477
Corporate interest expense	(5,322)	(6,019)	(14,688)	(17,591)
Reconciling Items [Member] | Homebuilding [Member] | Mid Atlantic [Member]
Segment Reporting Reconciling Item For Operating Profit Loss From Segment To Consolidated [Line Items]
Corporate capital allocation	31,960	28,743	87,911	78,412
Reconciling Items [Member] | Homebuilding [Member] | North East [Member]
Segment Reporting Reconciling Item For Operating Profit Loss From Segment To Consolidated [Line Items]
Corporate capital allocation	4,572	4,451	13,972	11,566
Reconciling Items [Member] | Homebuilding [Member] | Mid East [Member]
Segment Reporting Reconciling Item For Operating Profit Loss From Segment To Consolidated [Line Items]
Corporate capital allocation	7,366	7,472	21,523	20,079
Reconciling Items [Member] | Homebuilding [Member] | South East [Member]
Segment Reporting Reconciling Item For Operating Profit Loss From Segment To Consolidated [Line Items]
Corporate capital allocation	$ 6,134	$ 5,024	$ 17,200	$ 13,976