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Joint Ventures - Additional Information (Detail) $ in Thousands | 3 Months Ended |
--- | --- | ---
Sep. 30, 2018 USD ($) joint_venture lot | Dec. 31, 2017 USD ($)
Joint Ventures [Line Items] |  |
Aggregate investment | $ 31,750 |
Number of joint ventures | joint_venture | 6 |
Expected production of finished lots | lot | 6,900 |
Total lots controlled by company under the joint venture | lot | 3,550 |
Total lots either under contract with unrelated parties or not under the current contract | lot | 3,350 |
Additional funding commitments in the aggregate | $ 5,000 |
Number of joint ventures with additional funding commitment | joint_venture | 3 |
Number of joint ventures NVR is not primary beneficiary | joint_venture | 5 |
Other Assets [Member] |  |
Joint Ventures [Line Items] |  |
Aggregate investment | $ 31,750 | $ 49,000
Cost of Sales [Member] |  |
Joint Ventures [Line Items] |  |
Equity Method Investment, Other than Temporary Impairment | 7,400 |
EquityMethodInvestmentOtherThanTemporaryImpairmentCapitalizedInterestPortion | $ 760 |

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- Definition The portion of the other-than-temporary impairment charge related to interest previously capitalized to land under development inventory. + References No definition available. + Details
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- Definition Expected production of finished lots from joint ventures. + References No definition available. + Details
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- Definition Joint ventures. + References No definition available. + Details
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- Definition The number of joint ventures to which NVR has an additional funding commitment. + References No definition available. + Details
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- Definition This item represents an other than temporary decline in value that has been recognized against an investment accounted for under the equity method of accounting. The excess of the carrying amount over the fair value of the investment represents the amount of the write down which is or was reflected in earnings. The written down value is a new cost basis with the adjusted value of the investment becoming its new carrying value subject to the equity accounting method. Evidence of a loss in value might include, but would not necessarily be limited to, absence of an ability to recover the carrying amount of the investment or inability of the investee to sustain an earnings capacity which would justify the carrying amount of the investment. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 323 -SubTopic 10 -Section 35 -Paragraph 32 -URI http://asc.fasb.org/extlink&oid=114001220&loc=d3e32787-111569 + Details
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