Joint Ventures - Additional Information (Detail) $ in Thousands	Jun. 30, 2017 USD ($) Lot JointVenture	Dec. 31, 2016 USD ($)
Joint Ventures [Line Items]
Aggregate investment | $	$ 44,000
Number of joint ventures | JointVenture	6
Expected production of finished lots | Lot	7,350
Total lots controlled by company under the joint venture | Lot	4,050
Total lots either under contract with unrelated parties or not under the current contract | Lot	3,300
Additional funding commitments in the aggregate | $	$ 5,800
Number of joint ventures with additional funding commitment | JointVenture	3
Number of joint ventures NVR is not primary beneficiary | JointVenture	5
Other Assets [Member]
Joint Ventures [Line Items]
Aggregate investment | $	$ 43,600	$ 49,000