XML 70 R55.htm IDEA: XBRL DOCUMENT
v3.20.4

Related Party Transactions - Additional Information (Detail) - Elm Street $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2020 USD ($) lot | Dec. 31, 2019 USD ($) | Dec. 31, 2018 USD ($)
Related Party Transaction [Line Items] |  |  |
Related party forward lot purchase agreements purchase price | $ | $ 138,100 |  |
Number of related parties for forward lot purchase agreement | lot | 1 |  |
Market price of developed lots | $ | $ 60,200 | $ 44,600 | $ 36,100
Expected number of lots from joint venture with Elm Street | lot | 1,900 |  |

X
- Definition Expected yield of finished lots with remaining land of related party. + References No definition available. + Details
Name: | nvr_ExpectedYieldOfRelatedPartyLots
Namespace Prefix: | nvr_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | duration

X
- Definition Number of related parties for forward lot purchase agreement. + References No definition available. + Details
Name: | nvr_NumberOfRelatedPartiesForForwardLotPurchaseAgreement
Namespace Prefix: | nvr_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | duration

X
- Definition Related party lot purchase agreements purchase price. + References No definition available. + Details
Name: | nvr_RelatedPartyLotPurchaseAgreementsPurchasePrice
Namespace Prefix: | nvr_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
Name: | us-gaap_RelatedPartyTransactionLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Purchases during the period (excluding transactions that are eliminated in consolidated or combined financial statements) with related party. + References No definition available. + Details
Name: | us-gaap_RelatedPartyTransactionPurchasesFromRelatedParty
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Details
Name: | us-gaap_RelatedPartyTransactionsByRelatedPartyAxis=nvr_ElmStreetMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |