Segment Information, Nature of Operations, and Certain Concentrations - Depreciation and Amortization (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Segment Reporting Other Significant Reconciling Item [Line Items]
Consolidated depreciation and amortization	$ 22,269	$ 21,534	$ 17,614
Operating Segments [Member]
Segment Reporting Other Significant Reconciling Item [Line Items]
Consolidated depreciation and amortization	17,283	16,777	13,713
Operating Segments [Member] | Homebuilding [Member] | Mid Atlantic [Member]
Segment Reporting Other Significant Reconciling Item [Line Items]
Consolidated depreciation and amortization	8,089	7,876	6,489
Operating Segments [Member] | Homebuilding [Member] | North East [Member]
Segment Reporting Other Significant Reconciling Item [Line Items]
Consolidated depreciation and amortization	2,053	1,571	1,208
Operating Segments [Member] | Homebuilding [Member] | Mid East [Member]
Segment Reporting Other Significant Reconciling Item [Line Items]
Consolidated depreciation and amortization	3,748	4,003	3,212
Operating Segments [Member] | Homebuilding [Member] | South East [Member]
Segment Reporting Other Significant Reconciling Item [Line Items]
Consolidated depreciation and amortization	2,276	2,191	1,715
Operating Segments [Member] | Mortgage Banking [Member]
Segment Reporting Other Significant Reconciling Item [Line Items]
Consolidated depreciation and amortization	1,117	1,136	1,089
Consolidation adjustments and other [Member]
Segment Reporting Other Significant Reconciling Item [Line Items]
Consolidated depreciation and amortization	$ 4,986	$ 4,757	$ 3,901