Segment Disclosures - Revenues (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Segment Reporting, Revenue Reconciling Item [Line Items]
Revenues	$ 1,990,012	$ 1,911,264	$ 5,192,908	$ 5,398,469
Home Building [Member]
Segment Reporting, Revenue Reconciling Item [Line Items]
Revenues	1,920,751	1,873,331	5,065,216	5,273,985
Home Building [Member] | Mid Atlantic [Member]
Segment Reporting, Revenue Reconciling Item [Line Items]
Revenues	949,472	1,012,056	2,563,375	2,875,411
Home Building [Member] | North East [Member]
Segment Reporting, Revenue Reconciling Item [Line Items]
Revenues	157,973	120,478	362,328	364,909
Home Building [Member] | Mid East [Member]
Segment Reporting, Revenue Reconciling Item [Line Items]
Revenues	404,992	406,145	1,025,642	1,104,603
Home Building [Member] | South East [Member]
Segment Reporting, Revenue Reconciling Item [Line Items]
Revenues	408,314	334,652	1,113,871	929,062
Mortgage Banking [Member]
Segment Reporting, Revenue Reconciling Item [Line Items]
Revenues	$ 69,261	$ 37,933	$ 127,692	$ 124,484