Segment Information, Nature of Operations, and Certain Concentrations - Interest Expense (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Segment Reporting Other Significant Reconciling Item [Line Items]
Consolidated interest expense	$ 23,559	$ 23,140	$ 22,385
Homebuilding [Member]
Segment Reporting Other Significant Reconciling Item [Line Items]
Consolidated interest expense	22,918	22,591	21,840
Mortgage Banking [Member]
Segment Reporting Other Significant Reconciling Item [Line Items]
Consolidated interest expense	641	549	545
Operating Segments [Member]
Segment Reporting Other Significant Reconciling Item [Line Items]
Consolidated interest expense	171,860	152,736	117,100
Operating Segments [Member] | Homebuilding [Member] | Mid Atlantic [Member]
Segment Reporting Other Significant Reconciling Item [Line Items]
Consolidated interest expense	107,748	96,364	72,351
Operating Segments [Member] | Homebuilding [Member] | North East [Member]
Segment Reporting Other Significant Reconciling Item [Line Items]
Consolidated interest expense	16,991	12,114	9,466
Operating Segments [Member] | Homebuilding [Member] | Mid East [Member]
Segment Reporting Other Significant Reconciling Item [Line Items]
Consolidated interest expense	27,263	26,300	22,587
Operating Segments [Member] | Homebuilding [Member] | South East [Member]
Segment Reporting Other Significant Reconciling Item [Line Items]
Consolidated interest expense	19,217	17,409	12,151
Operating Segments [Member] | Mortgage Banking [Member]
Segment Reporting Other Significant Reconciling Item [Line Items]
Consolidated interest expense	641	549	545
Reconciling Items [Member]
Segment Reporting Other Significant Reconciling Item [Line Items]
Consolidated interest expense	22,869	22,544	21,743
Corporate capital allocation	(171,170)	(152,140)	(116,458)
Reconciling Items [Member] | Homebuilding [Member] | Mid Atlantic [Member]
Segment Reporting Other Significant Reconciling Item [Line Items]
Corporate capital allocation	(107,705)	(96,328)	(72,272)
Reconciling Items [Member] | Homebuilding [Member] | North East [Member]
Segment Reporting Other Significant Reconciling Item [Line Items]
Corporate capital allocation	(16,987)	(12,107)	(9,461)
Reconciling Items [Member] | Homebuilding [Member] | Mid East [Member]
Segment Reporting Other Significant Reconciling Item [Line Items]
Corporate capital allocation	(27,263)	(26,299)	(22,580)
Reconciling Items [Member] | Homebuilding [Member] | South East [Member]
Segment Reporting Other Significant Reconciling Item [Line Items]
Corporate capital allocation	$ (19,215)	$ (17,406)	$ (12,145)