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Present value of lessee's discounted obligation for lease payments from operating lease, classified as current.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 45
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=77888419&loc=SL77918627-209977

Name:	us-gaap_OperatingLeaseLiabilityCurrent
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Data Type:	xbrli:monetaryItemType
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Period Type:	instant

Present value of lessee's discounted obligation for lease payments from operating lease, classified as noncurrent.

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The amount of accumulated depreciation, by major property class, recorded on property subject to or available for lease as of the balance sheet date.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
-SubTopic 20
-Section 45
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=77907726&loc=d3e41460-112716

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
-SubTopic 20
-Section 50
-Paragraph 4
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=84164653&loc=d3e41551-112718

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Refers to the capitalization construction costs due to specific accounting regulations.

No definition available.

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Loss Contingency, Number of Subcontractors

No definition available.

Name:	vsec_LossContingencyNumberofSubcontractors
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The length of time the entity is under obligation to lease the asset.

No definition available.

Name:	vsec_TermOfLease
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Balance Type:	na
Period Type:	duration

Name:	us-gaap_LeaseArrangementTypeAxis=vsec_OperatingLeasesMember
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Name:	srt_RangeAxis=srt_MinimumMember
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Name:	srt_RangeAxis=srt_MaximumMember
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