XML 38 R62.htm IDEA: XBRL DOCUMENT
v2.4.0.6

Equity-Based Compensation, Profit Sharing and Deferred Compensation Plans - Equity-Based Compensation Plans (Parenthetical) (Detail) (USD $) | 12 Months Ended
--- | ---
Dec. 31, 2012
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |
Restricted share units exercise price | $ 0

X
- Definition Exercise price of restricted share units. + References No definition available. + Details
Name: | nvr_RestrictedShareUnitsExercisePrice
Namespace Prefix: | nvr_
Data Type: | num:perShareItemType
Balance Type: | na
Period Type: | duration

X
- Details
Name: | us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration