Segment Disclosures - Assets (Detail) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2014	Dec. 31, 2013	Sep. 30, 2013	Dec. 31, 2012
Segment Reporting, Asset Reconciling Item [Line Items]
Consolidated assets	$ 2,413,076	$ 2,486,148
Consolidated variable interest entity	6,232	7,268
Cash and cash equivalents	466,293	866,253	814,197	1,153,507
Contract land deposit reserve	(54,375)	(59,761)
Operating Segments [Member]
Segment Reporting, Asset Reconciling Item [Line Items]
Consolidated assets	1,722,477	1,427,205
Operating Segments [Member] | Homebuilding Mid Atlantic [Member]
Segment Reporting, Asset Reconciling Item [Line Items]
Consolidated assets	1,022,146	810,270
Operating Segments [Member] | Homebuilding North East [Member]
Segment Reporting, Asset Reconciling Item [Line Items]
Consolidated assets	108,597	84,958
Operating Segments [Member] | Homebuilding Mid East [Member]
Segment Reporting, Asset Reconciling Item [Line Items]
Consolidated assets	218,105	172,167
Operating Segments [Member] | Homebuilding South East [Member]
Segment Reporting, Asset Reconciling Item [Line Items]
Consolidated assets	148,140	106,389
Operating Segments [Member] | Mortgage Banking [Member]
Segment Reporting, Asset Reconciling Item [Line Items]
Consolidated assets	225,489	253,421
Reconciling Items Sub-Total [Member]
Segment Reporting, Asset Reconciling Item [Line Items]
Consolidated variable interest entity	6,232	7,268
Cash and cash equivalents	455,387	844,274
Deferred taxes	167,983	162,378
Intangible assets and goodwill	54,637	55,674
Contract land deposit reserve	(54,375)	(59,761)
Reconciling items sub-total	690,599	1,058,943
Consolidation adjustments and other [Member]
Segment Reporting, Asset Reconciling Item [Line Items]
Consolidated assets	$ 60,735	$ 49,110