Property Plant and Equipment ("PP&E") - Summary of Property Plant and Equipment (Detail) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Home Building
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	$ 165,525	$ 148,916
Finance Lease, Right-of-Use Asset, after Accumulated Amortization	15,772	7,051
Less: accumulated depreciation	(107,739)	(96,656)
Net Homebuilding PP&E	57,786	52,260
Home Building \| Office facilities and other
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	39,647	39,218
Home Building \| Model home furniture and fixtures
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	32,686	31,352
Home Building \| Production facilities
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	77,420	71,295
Mortgage Banking
Property, Plant and Equipment [Line Items]
Net Homebuilding PP&E	4,544	5,828
Mortgage Banking \| Office facilities and other
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	14,716	14,617
Less: accumulated depreciation	(10,172)	(8,789)
Net Homebuilding PP&E	$ 4,544	$ 5,828

Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

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Amount, after accumulated amortization, of right-of-use asset from finance lease.

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