XML 66 R48.htm IDEA: XBRL DOCUMENT
v3.8.0.1

Summary of Significant Accounting Policies - Warranty (Details) | 12 Months Ended
--- | ---
Dec. 31, 2017
Minimum |
Warranty |
Standard product warranty period | 1 year
Extended product warranty period | 1 year
Maximum |
Warranty |
Standard product warranty period | 2 years
Extended product warranty period | 4 years

X
- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
Name: | us-gaap_ProductWarrantyLiabilityLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Extended Warranty Period Related To Hardware Products + References No definition available. + Details
Name: | vdsi_ExtendedWarrantyPeriodRelatedToHardwareProducts
Namespace Prefix: | vdsi_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- Definition Standard product warranty period. + References No definition available. + Details
Name: | vdsi_StandardProductWarrantyPeriod
Namespace Prefix: | vdsi_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- Details
Name: | us-gaap_RangeAxis=us-gaap_MinimumMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_RangeAxis=us-gaap_MaximumMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |