Segment Disclosures - Corporate Capital Allocation Charge (Detail) (Corporate Capital Allocation [Member], USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014
Segment Reporting Other Significant Reconciling Item [Line Items]
Segment reporting reconciling amount for operating profit	$ 36,945	$ 28,966
Homebuilding Mid Atlantic [Member]
Segment Reporting Other Significant Reconciling Item [Line Items]
Segment reporting reconciling amount for operating profit	23,411	18,156
Homebuilding North East [Member]
Segment Reporting Other Significant Reconciling Item [Line Items]
Segment reporting reconciling amount for operating profit	3,310	2,449
Homebuilding Mid East [Member]
Segment Reporting Other Significant Reconciling Item [Line Items]
Segment reporting reconciling amount for operating profit	5,935	5,298
Homebuilding South East [Member]
Segment Reporting Other Significant Reconciling Item [Line Items]
Segment reporting reconciling amount for operating profit	$ 4,289	$ 3,063