Deferred Warranty Revenue and Warranty Reserve - Deferred Warranty Revenue (Detail) $ in Thousands	12 Months Ended
Dec. 31, 2016 USD ($)
Guarantees [Abstract]
2017	$ 22
2018	12
2019	3
Total	$ 37

The total amount of deferred revenue that will be recognized in future periods.

No definition available.

Name:	vdsi_DeferredRevenueEstimatedRevenueExpectedRecognized
Namespace Prefix:	vdsi_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration