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Amount charged against operating income increasing loss contingency liability, after adjustments to reduce previously estimated charges.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=25496072&loc=d3e14326-108349

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Reflects the estimated amount of loss from the specified contingency as of the balance sheet date.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
-Paragraph 4
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The floor amount as of the balance sheet date that the entity must expend to satisfy the terms of disclosed arrangements (excluding long-term commitments) in which the entity must commit resources to supply goods or services to one or more customers.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
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-Subparagraph (SX 210.9-03.17)
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Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
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-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.25)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
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-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03.(a)(19))
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- References

No definition available.

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Amount of judgment or litigation settlement over estimated amount.

No definition available.

Name:	vsec_LitigationSettlementOverEstimatedAmount
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Represents the number of bonded projects that had not yet been completed and the aggregate bonded amount on projects.

No definition available.

Name:	vsec_NumberOfBondedProjects
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The number of deaths of subcontractor employees related to fireworks explosion.

No definition available.

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Refers to number of subcontractors for lawsuits filed.

No definition available.