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Segment Information, Nature of Operations, and Certain Concentrations - Additional Information (Detail)	12 Months Ended
	Dec. 31, 2012 Joint_Ventures MetropolitanArea
Segment Reporting Information [Line Items]
Number of metropolitan areas Ryan Homes product are sold	27
Number of consolidated joint ventures	1
Revenue derived from Washington, D.C. and Baltimore, MD metropolitan areas	47.00%
Homebuilding [Member]
Segment Reporting Information [Line Items]
Number of reportable segments	4
Mortgage Banking [Member]
Segment Reporting Information [Line Items]
Number of reportable segments	1

X

- Definition

Number of consolidated joint ventures.

+ References

No definition available.

+ Details

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Namespace Prefix:	nvr_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

X

- Definition

The number of metropolitan areas that Ryan Homes products are sold in.

+ References

No definition available.

+ Details

Name:	nvr_NumberOfMetropolitanAreasSales
Namespace Prefix:	nvr_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

X

- Definition

Percentage of homebuilding revenue derived from Washington, D.C. and Baltimore, MD metropolitan areas.

+ References

No definition available.

+ Details

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Namespace Prefix:	nvr_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

X

- Definition

Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements.

+ References

No definition available.

+ Details

Name:	us-gaap_NumberOfReportableSegments
Namespace Prefix:	us-gaap_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

X

- Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
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Period Type:	duration