Segment Information, Nature of Operations, and Certain Concentrations - Revenues (Detail) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Segment Reporting Revenue Reconciling Item [Line Items]
Consolidated revenues									$ 5,159,008	$ 4,444,568	$ 4,211,267
Homebuilding [Member]
Segment Reporting Revenue Reconciling Item [Line Items]
Revenues	$ 1,528,084	$ 1,374,467	$ 1,221,111	$ 941,538	$ 1,306,632	$ 1,185,160	$ 1,084,080	$ 799,187	5,065,200	4,375,059	4,134,481
Homebuilding [Member] | Mid Atlantic [Member]
Segment Reporting Revenue Reconciling Item [Line Items]
Revenues									3,022,789	2,617,108	2,439,387
Homebuilding [Member] | North East [Member]
Segment Reporting Revenue Reconciling Item [Line Items]
Revenues									432,145	376,862	332,681
Homebuilding [Member] | Mid East [Member]
Segment Reporting Revenue Reconciling Item [Line Items]
Revenues									1,014,920	892,513	908,198
Homebuilding [Member] | South East [Member]
Segment Reporting Revenue Reconciling Item [Line Items]
Revenues									595,346	488,576	454,215
Mortgage Banking [Member]
Segment Reporting Revenue Reconciling Item [Line Items]
Mortgage Banking	$ 27,191	$ 27,884	$ 22,522	$ 16,211	$ 21,406	$ 18,006	$ 17,974	$ 12,123	$ 93,808	$ 69,509	$ 76,786