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Represents the amount of reduction of liability for payments made, effecting a change in the contingent consideration liability during the period.

No definition available.

Name:	nvee_BusinessCombinationContingentConsiderationLiabilityReductionOfLiabilityForPaymentsMade
Namespace Prefix:	nvee_
Data Type:	xbrli:monetaryItemType
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Commitments and Contingencies Disclosure [Roll Forward]

No definition available.

Name:	nvee_CommitmentsandContingenciesDisclosureRollForward
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Data Type:	xbrli:stringItemType
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Represents the amount of increase (reduction) of the contingent consideration liability during the period related to re-measurement of fair value.

No definition available.

Name:	nvee_IncreaseOfLiabilityRelatedToReMeasurementOfFairValue
Namespace Prefix:	nvee_
Data Type:	xbrli:monetaryItemType
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Period Type:	duration

Amount of liability recognized arising from contingent consideration in a business combination.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=120321790&loc=d3e6927-128479

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 35
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=116859824&loc=d3e6819-128478

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 25
-Paragraph 6
-URI http://asc.fasb.org/extlink&oid=6911189&loc=d3e6408-128476

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Amount of liability recognized arising from contingent consideration in a business combination, expected to be settled within one year or the normal operating cycle, if longer.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 25
-Paragraph 6
-URI http://asc.fasb.org/extlink&oid=6911189&loc=d3e6408-128476

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 35
-Paragraph 1
-Subparagraph b
-URI http://asc.fasb.org/extlink&oid=116859824&loc=d3e6819-128478

Name:	us-gaap_BusinessCombinationContingentConsiderationLiabilityCurrent
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Amount of liability recognized arising from contingent consideration in a business combination, expected to be settled beyond one year or the normal operating cycle, if longer.