Commitments and Contingencies - (VQW-765) - Additional Information (Detail)	9 Months Ended
Sep. 30, 2020
VQW-765
Commitments and Contingencies [Line Items]
Future percentage of royalty payments based net sales	mid-teens

Future Percentage Of Royalty Payments Based On Net Sales.

No definition available.

Name:	vnda_FuturePercentageOfRoyaltyPaymentsBasedOnNetSales
Namespace Prefix:	vnda_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration