XML 66 R50.htm IDEA: XBRL DOCUMENT
v3.8.0.1

Variable Interest Entities - Total Risk of Loss Related to Contract Land Deposits (Textual) (Detail) - lot | Dec. 31, 2017 | Dec. 31, 2016
--- | --- | ---
Variable Interest Entity, Reporting Entity Involvement, Maximum Loss Exposure [Abstract] |  |
Finished lots committed to purchase under specific performance obligations | 10 | 10

X
- Definition Finished lots committed to purchase under specific performance obligations. + References No definition available. + Details
Name: | nvr_FinishedLotsCommittedToPurchase
Namespace Prefix: | nvr_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | instant

X
- References No definition available. + Details
Name: | us-gaap_VariableInterestEntityReportingEntityInvolvementMaximumLossExposureAbstract
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration