Warrants - Narrative (Details) - USD ($)	9 Months Ended	12 Months Ended
Sep. 30, 2021	Dec. 31, 2020
Other Liabilities Disclosure [Abstract]
Number of warrants exercised and forfeited	0	0
Intrinsic value	$ 0

Class Of Warrant Or Right, Number Of Exercised Or Forfeited

No definition available.

Name:	vrna_ClassOfWarrantOrRightNumberOfExercisedOrForfeited
Namespace Prefix:	vrna_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration