Segment Disclosures - Revenues (Detail) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Segment Reporting, Revenue Reconciling Item [Line Items]
Revenues	$ 1,687,011	$ 1,529,414
Home Building [Member]
Segment Reporting, Revenue Reconciling Item [Line Items]
Revenues	1,643,206	1,490,093
Home Building [Member] | Mid Atlantic [Member]
Segment Reporting, Revenue Reconciling Item [Line Items]
Revenues	881,324	842,496
Home Building [Member] | North East [Member]
Segment Reporting, Revenue Reconciling Item [Line Items]
Revenues	122,627	122,714
Home Building [Member] | Mid East [Member]
Segment Reporting, Revenue Reconciling Item [Line Items]
Revenues	338,549	290,237
Home Building [Member] | South East [Member]
Segment Reporting, Revenue Reconciling Item [Line Items]
Revenues	300,706	234,646
Mortgage Banking [Member]
Segment Reporting, Revenue Reconciling Item [Line Items]
Revenues	$ 43,805	$ 39,321