Variable Interest Entities - Additional Information (Detail) $ in Thousands	12 Months Ended
	Dec. 31, 2020 USD ($) lot	Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)
Variable Interest Entity [Line Items]
Maximum range of deposits required under the purchase agreements	10.00%
Net Contract Land Deposit Impairment Recoveries	$ 25,600	$ (700)	$ 5,100
Contract Land Deposits	$ 439,833	$ 441,423
Variable Interest Entities
Variable Interest Entity [Line Items]
Maximum range of deposits required under the purchase agreements	10.00%
Lots controlled by NVR | lot	103,000
Contract land deposits in cash under Lot Purchase Agreements	$ 438,500
Letters of credit related to lots	$ 8,100
Contract on Raw Ground with Landowners
Variable Interest Entity [Line Items]
Lots controlled by NVR | lot	6,100
Letters of credit on raw land contracts	$ 100
Refundable deposits	1,000
Contract Land Deposits	$ 1,300