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Variable Interest Entities and Joint Ventures - Total Risk Related to Lot Options (Parenthetical) (Detail) | Dec. 31, 2012 Lot | Dec. 31, 2011 Lot
--- | --- | ---
Variable Interest Entity [Line Items] |  |
Finished lots committed to purchase under specific performance obligations | 71 | 92

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

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